Question

Katie opened her bank account with $710 and withdrew $35 per week. Diana opened her bank account with $570 and withdrew $25 weekly. In how many weeks with their bank accounts be equal? *

Answer 1

In 10 weeks

Explanation:

Supposing the bank does not pay any interest, after n weeks Katie will have

$710 - n35

and Diana will have

$570 - n25

We must find then a number n such that

710 - n35 = 570 - n25

Isolate n

710 - 570 = n35 - n25

140 = 10n

Hence

n = 140/10 = 14

So, Katie and Diana will have the same amount of money after 14 weeks.