Question

The sum of the two numbers is 36 and their difference is 9. Find the average of the two numbers

Answer 1

Answer:

The required average of the two numbers is 18

Step-by-step explanation:

Given :

• The sum of the two numbers is 36
• The difference of the two numbers is 9

To find :

the average of the two numbers

Solution :

Let the two numbers be x and y. (x > y)

Their sum = 36 :

x + y = 36 –(1)

Their difference = 9 :

x – y = 9 –(2)

Add both equations (1) and (2),

x + y + x – y = 36 + 9

2x = 45

x = 45/2

x = 22.5

Substitute x = 22.5 in equation (1),

22.5 + y = 36

y = 36 – 22.5

y = 13.5

Therefore, the two numbers are 22.5 and 13.5

Average :

Average = sum of observations/number of observations

Average of the two numbers :

= (22.5 + 13.5)/2

= 36/2

= 18