Martha, Peter, and Kenneth have a total of $82 in their wallets. Martha has $10 more than Peter. Kenneth has 2 times what Martha has. How much do they have in their wallets?

Answer 1

You can start by creating an equation that says Martha(m), Peter(p), and Kenneth(k) have $82 in total.

m + p + k = 82

Next substitute in information so that you replace all but one variable. "Martha has $10 more than Peter" --> that means we can substitute m for p + 10.

(p + 10) + p + k = 82

Then "Kenneth has 2 times what Martha has" --> k = 2 * m = 2 * (p+10)

(p + 10) + p + 2 * (p + 10) = 82

p + 10 + p + 2p + 20 = 82

4p + 30 = 82

4p = 52

p = 13

Peter has $13 which means Martha has $23 ($13 + $10) and Kenneth has $46 (2 times Martha's, $23).

Let's double check! 13+23+46 = 82