Question

Jen was making cake pops for the bake sale. After 3 hours, she had completed half of the work. She called Maryna for help and together they finished everything in half an hour. How long would it take Maryna to finish the job alone if she replaced Jen after Jen baked for 3 hours? PLS HELP!!!!!!!!

Answer 1

0.6 hours

Explanation:

Let's say J is Jen's speed (cake pops per hour), and let's say M is Maryna's speed (cake pops per hour).

Let's say there are 12 cake pops total that need to be made. Jen made half of the cake pops in 3 hours, so she made 6 cake pops in 3 hours. So her speed is 2 cake pops per hour.

Then, Jen and Maryna made the other half of the cake pops in 1/2 hour. Therefore, their combined speed is:

J + M = 6 cake pops / (1/2 hr)

J + M = 12

2 + M = 12

M = 10

So Maryna can make 10 cake pops per hour.

If Maryna was working alone, the amount of time it would take her to make 6 cake pops is:

6 cake pops / (10 cake pops per hour) = 0.6 hours

It would take 0.6 hours, or 36 minutes.