Question

Cinderella currently does chores for 120 minutes per day. Her evil step-mother wants her to do chores for 200 minutes each day. Each week, her step-mother is increasing her number of minutes by 10%. Her fairy godmother suggested Cinderella negotiate (work) with her step-mother for an increase of 5% per week.

Write an exponential function to represent how long Cinderella will do chores after x number of weeks if she goes along with her step-mother and does not take her fairy godmother’s advice.

To show an exponent, hit "shift-6" (^) and then type your exponent. For example, to show x2 I would type x^2

Answer 1

P = 120 * 1.1^x

Explanation:

The generic equation for an exponencial function is:

P = Po * (1+r)^t

Where P is the final value, Po is the inicial value, r is the rate and t is the amount of time.

In this problem, we have that Po = 120, r = 10% = 0.1 and the time t is the variable x. So we can write the equation:

P = 120 * (1+0.1)^x

P = 120 * 1.1^x

Where P is how long Cinderella will do chores after x weeks.