Amal gets newsletters by e-mail. He gets one for math every 5 days, one for english every 10 days, and one for science every 8 days. If he got all three today, how many more days will it be until he gets all three newsletters on the same day again?
We can find how many more days it will be until he gets all 3 newsletters by finding the least common multiple of 5, 8 and 10.
LCM(5, 8, 10)=40, so it will be 40 more days until he gets all three on the same day again.