Explanation

The sum of the values is calculated as the average multiplied by the number of values: 30 * 4 = 120.

Therefore, the sum of the values is 120.

Explanation

The average is the sum divided by the number of quantities:

Average = Sum / n

115 = 1840 / n

To find 'n', multiply both sides by 'n' and then divide by 115:

n = 1840 / 115

n = 16

Explanation

Find how many man-days to complete the road:

70*35 = 2450 man-days

Let d = days required for 40 men to do it.

40d = 2450

d=402450​=61.25

Explanation

120 men can do work = 30 days

1 man can do this work = 120 x 30 = 3600 days

80 men can do this work = 3600/80 = 45 days

Explanation

Total students = 26

Students who like football = 21

Students who like cricket = 14

Let x be the number of students who like both football and cricket.

Using the formula:

(Football ∪ Cricket) = Football + Cricket – Both

So,

26 = 21 + 14 – x

26 = 35 – x

x = 35 – 26

x = 9