Dorothy and Rosanne are baking cookies for a party. Working alone, Rosanne can finish the cookies in 6 hours. Dorothy can finish them in 8 hours if she is working alone. How long will it take them to bake the cookies if they are working together? Round your answer to the nearest hundredth if necessary. (1 point) Responses

A. 7.00 hours \
B. 3.43 hours
C. 0.29 hours
D. 14.00 hours

1 answer

To solve this problem, we can use the formula:

1/total time = 1/time taken by Rosanne + 1/time taken by Dorothy

Plugging in the values, we get:

1/total time = 1/6 + 1/8
1/total time = 4/24 + 3/24
1/total time = 7/24
total time = 24/7
total time ≈ 3.43 hours

Therefore, the answer is:

B. 3.43 hours