Answer:
Number of hours= 20 hours
Step-by-step explanation:
Giving the following information:
Net savings (babysitting)= 250 - 110= $140
Rate per hour= $7
To calculate the number of hours that Melissa worked as a babysitter, we need to use the following formula:
Number of hours= net savings / rate per hour
Number of hours= 140 / 7
Number of hours= 20 hours