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Prime Factors, HCF and LCM

Prime Factors, HCF and LCM

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Question 10
51%

Alarm X sounds every 15 seconds.
Alarm Y sounds every 20 seconds.
Alarm Z sounds every 25 seconds.

All three alarms sound at the same time.

Work out how long it will take for all three alarms to sound at the same time again.

[3]
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Prime Factors, HCF and LCM Questions

  1. GCSE
  2. /Maths
  3. /Prime Factors, HCF and LCM

59 exam-style questions on Edexcel GCSE Maths Prime Factors, HCF and LCM. Each one has a worked solution and a mark scheme showing where the marks go.

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