Question

if Mary starts with $10 in her savings account and wants to add $20 each week to save for a new phone that costs $150, how many weeks will she need to save before she has enough money?

Answer 1

7 weeks.

Explanation:

We know Mary starts with $10 in her account, so now we just find out how much more money she needs to save:

150 - 10 = 140

Now, all we have to do is find out how many times 20 fits into 140, since she wants to add $20 each week to her account:

140/20 = 7

Hence, it will take Mary 7 weeks before she has enough money for a new phone.