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HomeQuestion 1OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Solve carefully: Write the prime factorization of 180, then use it to find the HCF and LCM of 180 and 252.
Secondary 1Secondary 1Maths revision
Prime Numbers, HCF, and LCM
Build confidence with prime numbers, hcf, and lcm through short revision prompts and exam-style checks.
Focus points
✓Review the core ideas in prime numbers, hcf, and lcm.
✓Solve routine questions with clear working and good notation.
✓Apply the topic in short exam-style questions.
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The Wise Owl
Guides study flow, revision planning, and calmer focus sessions.
Practice setQuestion lineup
Mark each one done as you go — finish them all to claim your chips.
100 revision prompts
Question 2OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Show full working for: Three bells ring every 12, 18, and 30 minutes. If they ring together at 8:00 a.m., when will they next ring together?
Question 3OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Answer this exam-style prompt: Write the prime factorization of 180, then use it to find the HCF and LCM of 180 and 252.
Question 4OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Write down the key method, then solve: Three bells ring every 12, 18, and 30 minutes. If they ring together at 8:00 a.m., when will they next ring together?
Question 5OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Work this out and simplify your final answer: Write the prime factorization of 180, then use it to find the HCF and LCM of 180 and 252.
Question 6OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Set out your steps clearly for: Three bells ring every 12, 18, and 30 minutes. If they ring together at 8:00 a.m., when will they next ring together?
Question 7OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Find the answer and state your method for: Write the prime factorization of 180, then use it to find the HCF and LCM of 180 and 252.
Question 8OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Complete this revision check: Three bells ring every 12, 18, and 30 minutes. If they ring together at 8:00 a.m., when will they next ring together?
Question 9OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Solve and check your result for: Write the prime factorization of 180, then use it to find the HCF and LCM of 180 and 252.
Question 10OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Use accurate notation to answer: Three bells ring every 12, 18, and 30 minutes. If they ring together at 8:00 a.m., when will they next ring together?
Question 11OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Solve carefully: Write the prime factorization of 180, then use it to find the HCF and LCM of 180 and 252.
Question 12OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Show full working for: Three bells ring every 12, 18, and 30 minutes. If they ring together at 8:00 a.m., when will they next ring together?
Question 13OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Answer this exam-style prompt: Write the prime factorization of 180, then use it to find the HCF and LCM of 180 and 252.
Question 14OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Write down the key method, then solve: Three bells ring every 12, 18, and 30 minutes. If they ring together at 8:00 a.m., when will they next ring together?
Question 15OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Work this out and simplify your final answer: Write the prime factorization of 180, then use it to find the HCF and LCM of 180 and 252.
Question 16OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Set out your steps clearly for: Three bells ring every 12, 18, and 30 minutes. If they ring together at 8:00 a.m., when will they next ring together?
Question 17OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Explain which rule or property is most important in prime numbers, hcf, and lcm and illustrate it with a worked example.
Question 18OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Write one easier and one harder prime numbers, hcf, and lcm question, then solve both.
Question 19OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Describe a common mistake students make in prime numbers, hcf, and lcm and correct it with an example.
Question 20OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Turn one of today’s prime numbers, hcf, and lcm questions into a short word problem and solve it.
Question 21OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Create a similar prime numbers, hcf, and lcm question of your own and solve it fully.
Question 22OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Explain which rule or property is most important in prime numbers, hcf, and lcm and illustrate it with a worked example.
Question 23OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Write one easier and one harder prime numbers, hcf, and lcm question, then solve both.
Question 24OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Describe a common mistake students make in prime numbers, hcf, and lcm and correct it with an example.
Question 25OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Turn one of today’s prime numbers, hcf, and lcm questions into a short word problem and solve it.
Question 26OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Create a similar prime numbers, hcf, and lcm question of your own and solve it fully.
Question 27OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Explain which rule or property is most important in prime numbers, hcf, and lcm and illustrate it with a worked example.
Question 28OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Write one easier and one harder prime numbers, hcf, and lcm question, then solve both.
Question 29OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Describe a common mistake students make in prime numbers, hcf, and lcm and correct it with an example.
Question 30OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Turn one of today’s prime numbers, hcf, and lcm questions into a short word problem and solve it.
Question 31OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Create a similar prime numbers, hcf, and lcm question of your own and solve it fully.
Question 32OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Explain which rule or property is most important in prime numbers, hcf, and lcm and illustrate it with a worked example.
Question 33OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Write one easier and one harder prime numbers, hcf, and lcm question, then solve both.
Question 34OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Describe a common mistake students make in prime numbers, hcf, and lcm and correct it with an example.
Question 35OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Turn one of today’s prime numbers, hcf, and lcm questions into a short word problem and solve it.
Question 36OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Create a similar prime numbers, hcf, and lcm question of your own and solve it fully.
Question 37OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Explain which rule or property is most important in prime numbers, hcf, and lcm and illustrate it with a worked example.
Question 38OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Write one easier and one harder prime numbers, hcf, and lcm question, then solve both.
Question 39OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Describe a common mistake students make in prime numbers, hcf, and lcm and correct it with an example.
Question 40OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Turn one of today’s prime numbers, hcf, and lcm questions into a short word problem and solve it.
Question 41OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Create a similar prime numbers, hcf, and lcm question of your own and solve it fully.
Question 42OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Explain which rule or property is most important in prime numbers, hcf, and lcm and illustrate it with a worked example.
Question 43OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Write one easier and one harder prime numbers, hcf, and lcm question, then solve both.
Question 44OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Describe a common mistake students make in prime numbers, hcf, and lcm and correct it with an example.
Question 45OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Turn one of today’s prime numbers, hcf, and lcm questions into a short word problem and solve it.
Question 46OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Create a similar prime numbers, hcf, and lcm question of your own and solve it fully.
Question 47OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Explain which rule or property is most important in prime numbers, hcf, and lcm and illustrate it with a worked example.
Question 48OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Write one easier and one harder prime numbers, hcf, and lcm question, then solve both.
Question 49OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Describe a common mistake students make in prime numbers, hcf, and lcm and correct it with an example.
Question 50OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Turn one of today’s prime numbers, hcf, and lcm questions into a short word problem and solve it.
Question 51OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Create a similar prime numbers, hcf, and lcm question of your own and solve it fully.
Question 52OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Explain which rule or property is most important in prime numbers, hcf, and lcm and illustrate it with a worked example.
Question 53OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Write one easier and one harder prime numbers, hcf, and lcm question, then solve both.
Question 54OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Describe a common mistake students make in prime numbers, hcf, and lcm and correct it with an example.
Question 55OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Turn one of today’s prime numbers, hcf, and lcm questions into a short word problem and solve it.
Question 56OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Create a similar prime numbers, hcf, and lcm question of your own and solve it fully.
Question 57OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Explain which rule or property is most important in prime numbers, hcf, and lcm and illustrate it with a worked example.
Question 58OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Write one easier and one harder prime numbers, hcf, and lcm question, then solve both.
Question 59OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Describe a common mistake students make in prime numbers, hcf, and lcm and correct it with an example.
Question 60OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Turn one of today’s prime numbers, hcf, and lcm questions into a short word problem and solve it.
Question 61OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Create a similar prime numbers, hcf, and lcm question of your own and solve it fully.
Question 62OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Explain which rule or property is most important in prime numbers, hcf, and lcm and illustrate it with a worked example.
Question 63OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Write one easier and one harder prime numbers, hcf, and lcm question, then solve both.
Question 64OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Describe a common mistake students make in prime numbers, hcf, and lcm and correct it with an example.
Question 65OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Turn one of today’s prime numbers, hcf, and lcm questions into a short word problem and solve it.
Question 66OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Create a similar prime numbers, hcf, and lcm question of your own and solve it fully.
Question 67OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Explain which rule or property is most important in prime numbers, hcf, and lcm and illustrate it with a worked example.
Question 68OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Write one easier and one harder prime numbers, hcf, and lcm question, then solve both.
Question 69OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Describe a common mistake students make in prime numbers, hcf, and lcm and correct it with an example.
Question 70OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Turn one of today’s prime numbers, hcf, and lcm questions into a short word problem and solve it.
Question 71OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Create a similar prime numbers, hcf, and lcm question of your own and solve it fully.
Question 72OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Explain which rule or property is most important in prime numbers, hcf, and lcm and illustrate it with a worked example.
Question 73OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Write one easier and one harder prime numbers, hcf, and lcm question, then solve both.
Question 74OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Describe a common mistake students make in prime numbers, hcf, and lcm and correct it with an example.
Question 75OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Turn one of today’s prime numbers, hcf, and lcm questions into a short word problem and solve it.
Question 76OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Create a similar prime numbers, hcf, and lcm question of your own and solve it fully.
Question 77OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Explain which rule or property is most important in prime numbers, hcf, and lcm and illustrate it with a worked example.
Question 78OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Write one easier and one harder prime numbers, hcf, and lcm question, then solve both.
Question 79OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Describe a common mistake students make in prime numbers, hcf, and lcm and correct it with an example.
Question 80OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice)
Turn one of today’s prime numbers, hcf, and lcm questions into a short word problem and solve it.
Question 81OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice) / Free Online Revision extended practice
Create a similar prime numbers, hcf, and lcm question of your own and solve it fully.
Question 82OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice) / Free Online Revision extended practice
Explain which rule or property is most important in prime numbers, hcf, and lcm and illustrate it with a worked example.
Question 83OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice) / Free Online Revision extended practice
Write one easier and one harder prime numbers, hcf, and lcm question, then solve both.
Question 84OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice) / Free Online Revision extended practice
Describe a common mistake students make in prime numbers, hcf, and lcm and correct it with an example.
Question 85OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice) / Free Online Revision extended practice
Turn one of today’s prime numbers, hcf, and lcm questions into a short word problem and solve it.
Question 86OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice) / Free Online Revision extended practice
Create a similar prime numbers, hcf, and lcm question of your own and solve it fully.
Question 87OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice) / Free Online Revision extended practice
Explain which rule or property is most important in prime numbers, hcf, and lcm and illustrate it with a worked example.
Question 88OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice) / Free Online Revision extended practice
Write one easier and one harder prime numbers, hcf, and lcm question, then solve both.
Question 89OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice) / Free Online Revision extended practice
Describe a common mistake students make in prime numbers, hcf, and lcm and correct it with an example.
Question 90OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice) / Free Online Revision extended practice
Turn one of today’s prime numbers, hcf, and lcm questions into a short word problem and solve it.
Question 91OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice) / Free Online Revision extended practice
Create a similar prime numbers, hcf, and lcm question of your own and solve it fully.
Question 92OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice) / Free Online Revision extended practice
Explain which rule or property is most important in prime numbers, hcf, and lcm and illustrate it with a worked example.
Question 93OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice) / Free Online Revision extended practice
Write one easier and one harder prime numbers, hcf, and lcm question, then solve both.
Question 94OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice) / Free Online Revision extended practice
Describe a common mistake students make in prime numbers, hcf, and lcm and correct it with an example.
Question 95OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice) / Free Online Revision extended practice
Turn one of today’s prime numbers, hcf, and lcm questions into a short word problem and solve it.
Question 96OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice) / Free Online Revision extended practice
Create a similar prime numbers, hcf, and lcm question of your own and solve it fully.
Question 97OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice) / Free Online Revision extended practice
Explain which rule or property is most important in prime numbers, hcf, and lcm and illustrate it with a worked example.
Question 98OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice) / Free Online Revision extended practice
Write one easier and one harder prime numbers, hcf, and lcm question, then solve both.
Question 99OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice) / Free Online Revision extended practice
Describe a common mistake students make in prime numbers, hcf, and lcm and correct it with an example.
Question 100OpenStax Prealgebra 2e / CK-12 FlexMath (paraphrased practice) / Free Online Revision extended practice
Turn one of today’s prime numbers, hcf, and lcm questions into a short word problem and solve it.