Question

Two large and 1 small pumps can fill a swimming pool in 4 hours. One large and 3 small pumps can also fill the same swimming pool in 4 hours. How many hours will it take 4 large and 4 small pumps to fill the swimming pool.(We assume that all large pumps are similar and all small pumps are also similar.)

Answer 1

Step-by-step explanation: We can start the problem by using the principle of Proportional Equivalents. We can write two equations based on the given information:

Let's say that the rate of filling the pool with one large pump is x and the rate of filling the pool with one small pump is y.

Then, we can write the following two equations:

2x + 1y = 1/4 (because two large and one small pump can fill the pool in 4 hours)

1x + 3y = 1/4 (because one large and three small pumps can fill the pool in 4 hours)

Now we have two equations with two unknowns, x and y. We can solve for x and y using either substitution or elimination method. Let's use substitution method.

Solving for x:

From equation (1), we have 2x = 1/4 - 1y

Substituting this value of x in equation (2), we get:

1 (1/4 - 1y) + 3y = 1/4

Expanding and simplifying, we get:

1/4 - 1 + 3y = 1/4

3y = 1/2

y = 1/6

So, the rate of filling the pool with one small pump is 1/6.

Now that we have found the value of y, we can find the value of x.

x = 1/4 - 1y = 1/4 - 1 * 1/6 = 1/4 - 1/6 = 1/12

So, the rate of filling the pool with one large pump is 1/12.

Now that we have found the rate of filling the pool with each large and small pump, we can find the time it will take 4 large and 4 small pumps to fill the pool.

Let's call the rate of filling the pool with 4 large and 4 small pumps as R.

Then, R = 4 * 1/12 + 4 * 1/6 = 1/3

So, it will take 1/R = 3 hours to fill the pool with 4 large and 4 small pumps.