# How to do this application question 3?

##### 2 Answers

#### Answer:

#### Explanation:

Let **Problem.**

We are given that, the amt. of water decreases at a constant rate.

This means that,

**separable variable type Diff. Eqn.**

To get its **General Solution (GS), integrating term-wise,**

To determine the consts.

Solving

Then,

**desired relation!**

#### Answer:

Capacity of the tank **L = 5400 litres** , rate of decrease of water - **x = 120 litres per day**

#### Explanation:

Given : L - total volume of the tank

After 20 days

After (20 + 15) days,

Subtracting Eqn (2) from (10,

Substituting value of x in Equation (1),

L = 3000 + 2400 = 5400 litres#