Question

Select the correct answer. The time it takes to clean up after an anniversary party varies inversely as the number of people cleaning. If 3 people work together to clean, it will take them 90 minutes. How long will it take if the number of people cleaning is increased to 5? A. 54 minutes B. 72 minutes C. 150 minutes D. 162 minutes

Answer 1

Answer:

A. 54 minutes

Step-by-step explanation:

Given that:

Number of people working together to clean = 3

Time taken for cleaning when 3 people are working = 90 minutes

To find:

If the number of people are increased to 5, what will be the total time taken ?

Solution:

Formula for Total work is given as following:

Total work = Total men working multiplied with Time for which they work.

i.e.

$W = M \times T$

Here, we are given two situations:

$M_1$ = 3

$T_1$ = 90 minutes

$M_2$ = 5

$T_2$ = ?

Here, Total work in the two situations is same.

i.e. $W_1 = W_2$

$3\times 90 = 5 \times T_2\\\Rightarrow T_2 = \dfrac{270}{5}\\\Rightarrow \bold{T_2 = 54\ min}$

Therefore, the answer is:

A. 54 minutes

Answer 2

Answer:

54 mins

Step-by-step explanation: