Rosita can wax her car in 2 hours or 120 minutes. When she works together with Helga, they can wax the car in 45 minutes. How lo

Question

4 years ago

13

ng would it take Helga, working by herself, to wax the car?

1 answer:

Mashcka [7] · Answer 1 · 2021-11-29T14:16:10+03:00

<h2>Time taken by Helga to wax the car is 72 minutes</h2>

Step-by-step explanation:

Let w be the work of waxing.

Rosita can wax her car in 2 hours or 120 minutes.

Time taken by Rosita = 120 minutes

$\texttt{Rate of Rosita = }\frac{W}{120}$

Let time taken by Helga be t,

$\texttt{Rate of Helga = }\frac{W}{t}$

When she works together with Helga, they can wax the car in 45 minutes.

We have

$\frac{W}{\frac{W}{120}+\frac{W}{t}}=45\\\\120t=45(120+t)\\\\120t=5400+45t\\\\t=72minutes$

Time taken by Helga to wax the car is 72 minutes