1997 PMWC Problems/Problem I3

Problem

Peter is ill. He has to take medicine $A$ every $8$ hours, medicine $B$ every $5$ hours and medicine $C$ every $10$ hours. If he took all three medicines at $7$ a.m. on Tuesday, when will he take them altogether again?


Solution

$\operatorname{lcm}(8,5,10) = 40$, so he will consume the pills together forty hours afterwards or one day and 16 hours. That will be 11 p.m. Wednesday.

See Also

1997 PMWC (Problems)
Preceded by
Problem I2
Followed by
Problem I4
I: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
T: 1 2 3 4 5 6 7 8 9 10