Bob can paint a fence in 12 hours, and working with Jen can paint a fence in 4 hours. How long would it have taken Jen to paint the fence alone?

6 hours

Step-by-step explanation:

For Bob

12 hours = 1 fence

1 hour = 1/12 fence

Together Bob and Jen

4 hours = 1 fence

1 hour = 1/4 fence

Now, for Jen:

1 hour = 1/4 - 1/12= 3/12 - 1/12 = 2/12=1/6

Find the amount of time Jen will need:

1/6 fence = 1 hour

1 fence = 6 hour

if x decreases by 4 then y increases by 10

step-by-step explanation:

amount of oatypop that contains the prize = 40%

amount   of oatypop which doesn't contain the prize = (100-40)=60%

probability that hannah will win a prize

    = s +f s +f f s+ff   f s+ff f f s+ infinity.where f= failure,s= success

=   or 60%

probability that hannah only has to buy 3 or less boxes before getting a prize= (s) and ( f s) and (ff s) and (f f f s)

        = = 87.04 %  

step-by-step explanation: