Question 40
MediumOriginal questionWhat is the smallest number which, when divided by 6, 8 and 15, leaves a remainder of 2 in each case?
Show the answer and explanation
CorrectNot quiteAnswer C
Correct answer: C
Explanation
A number that leaves the same remainder 2 under all three divisors is 2 more than a common multiple of all three.
So find the LCM first: , , , giving .
The smallest such number is therefore .
Check: .
Worth noting
The 120 on offer is the LCM itself, which leaves remainder 0, not 2.
- Concept
- LCM with a common remainder
- Typical timeTypical
- 70 s
- Your timeYours
- —
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