Question

Hannah can paint a room in 15 hours. Destiny can paint the same room in 9 hours. How long does it take for both Hannah and Destiny to paint the room it they are working together hours = O No solution

Answer 1

Hanna can paint a room in 15 hours, this means she paints 1/15 of the room in an hour. Similarly Destiny paints 1/9 of the room in an hour.

Hence they paint

$\begin{gathered} \frac{1}{15}+\frac{1}{9}=\frac{9+15}{135} \\ =\frac{24}{135} \\ =\frac{8}{45} \end{gathered}$

together in an hour.

This means that they took

$\frac{45}{8}=5.625$

hours to paint the room together. This is the same