Problem / game
First name
Jeremy
School
Garden International School
School's Twitter handle
@gismalaysia
Country
Age
11
Yes, any 3 numbers picked from a set of 5 numbers will be a multiple of 3 when added. Why? Because if the average of 3 numbers from a set of 5 is a whole number with no decimal places, then those numbers add up to a multiple of 3.
For example, if 98, 85, 83, 29 and 74 were my 5 numbers to choose from, I could choose 74, 83 and 98 as my 3 numbers that add up to a multiple of 3 because the average of these 3 numbers is:74+83+98/amount of numbers (3)
=85x3/3
85