# The rainfall (in mm) in a city on 7 days of a certain week as recorded as follows:

(i) Find the range of the rainfall in the above data

(ii) Find the mean rainfall of the week

(iii) On how many days was the rainfall less than the mean rainfall?

**Solution:**

(i)Highest of the rainfall (in mm) = 20.5 Lowest of the rainfall (in mm) = 0.0

Range of the rainfall = Highest rainfall – Lowest rainfall

= 20.5 – 0.0

= 20. 5 mm

(ii)Total number of days = 7

Record of the rainfall (in mm) = 0.0, 12.2, 2.1, 0.0, 20.5, 5.5, 1.0

Mean of the rainfall (in mm) = sum of rainfalls (in mm)/Number of days

= (0.0 + 12.2 + 2.1 + 0.0 + 20.5 + 5.5 +1.0)/7

= 41.3/7

= 5.9mm

(iii) On 5 days rainfall was less than the mean rainfall i.e., Monday, Wednesday, Thursday, Saturday and Sunday.

**Video Solution:**

## The rainfall (in mm) in a city on 7 days of a certain week as recorded as follows:(i) Find the range of the rainfall in the above data. (ii) Find the mean rainfall of the week. (iii) On how many days was the rainfall less than the mean rainfall?

### NCERT Solutions Class 7 Maths - Chapter 3 Exercise 3.1 Question 8

The rainfall (in mm) in a city on 7 days of a certain week as recorded as follows:(i) Find the range of the rainfall in the above data. (ii) Find the mean rainfall of the week. (iii) On how many days was the rainfall less than the mean rainfall?

i) Range of the rainfall is equal to 20.5mm, ii) Mean of the rainfall is equal to 5.9mm, iii) On 5 days rainfall was less than the mean rainfall i.e., Monday, Wednesday, Thursday, Saturday and Sunday