Answer:
<em>The total number of weeks Michelle needs to save is 29.</em>
Step-by-step explanation:
Michelle plans to save $1185 in a number of weeks to determine later.
In the first 7 weeks, she will save $45 each week for a total of
$45 * 7 = $315
In the next 8 weeks, she will save $30 each week for a total of:
$30 * 8 = $240
During these 15 weeks, she has saved
$315 + $240 = $555
She still has a remaining $1185 - $555 = $630 to save.
Those $630 will be saved in a number of weeks at $45 per week, thus the number of weeks is:
$630 / $45 = 14 weeks
Total weeks = 15 + 14 = 29
The total number of weeks Michelle needs to save is 29.
