A tank on a building has enough water to supply 20 families living there for 6 days. If 10 more families move in there Class 8

A tank on a building has enough water to supply 20 families living there for 6 days. If 10 more families move in there Class 8

Question 1.

A tank on a building has enough water to supply 20 families living there for 6 days. If 10 more families move in there, how long will the water last? What assumptions do you need to make to work out this problem? Class 8

Solution:

If the number of families increases, then the water will last for less days. So, it is inverse proportion.

Let the water will last for x days.

Hence, 20 × 6 = (20 + 10) × x

or x = [latex]\frac{20 \times 6}{30}[/latex] = 4 days.

Question 2.

Fill in the average number of hours each living being sleeps in a day by looking at the charts. Select the appropriate hours from this list : 15, 2.5, 20, 8, 3.5, 13, 10.5, 18. Class 8

Solution:

Their sleeping time are respectively :

3.5, 2.5, 8, 10.5, 13, 15, 18 and 20 hours.