NCERT Exemplar Solutions
Class 6 - Mathematics - Unit 7: Algebra - Problems and Solutions
Question 90

Question. 90

In a village, there are 8 water tanks to collect rain water. On a particular day, x litres of rain water is collected per tank. If 100 litres of water was already there in one of the tanks, what is the total amount of water in the tanks on that day?

Answer:

8x + 100 L

Detailed Answer with Explanation:

What is given?

  • There are 8 water tanks.
  • Each tank collects (x) litres of rain water today.
  • One tank already had 100 litres before today.

Step 1: Find the water collected from rain today in all 8 tanks.

Water per tank today = (x) litres

Number of tanks = (8)

Total water collected today = (8 imes x)

So, (8 imes x = 8x) litres

Step 2: Add the water that was already in one tank.

Already present water = (100) litres

Total water in all tanks today = (8x + 100) litres

Final Answer: (8x + 100) litres


Quick check (optional): Suppose (x = 50) litres.

Today’s collected water = (8 imes 50 = 400) litres

Total = (400 + 100 = 500) litres

This matches the formula (8x + 100) when (x = 50).

NCERT Exemplar Solutions Class 6 – Mathematics – Unit 7: Algebra – Problems and Solutions | Detailed Answers