Michael started a savings account with $300. after 4 weeks, he had $350, abd after 9 weeks, he had $400. what is the rate of change?

Step-by-step explanation:

The initial amount was $300 and the final amount $350.  This $50 change occurred in 4 weeks.  Thus, the rate of change was

  $50

= $12.50/week for the first four weeks

 4 wks

For the first nine weeks, the rate of change was

$400-$300          $100

= = $0.11/week.

       9 wks               9 wks

Note that this second result makes little sense.  Ensure that you have copied this problem down correctly.