Question

There are three numbers. Average of three numbers is 85. If the second number is 25 more than the first number and third number is twice the second number. Find the second and third number.
1. 10 and 20
2. 70 and 140
3. 100 and 200
4. 50 and 100

Answer 1

Correct Answer - Option 2 : 70 and 140

Given

Average of three numbers = 85

Second number = first number + 25

Third number = 2(Second number)

Formula used

Average = Sum of all observation/Number of observation

Calculation

Let the first number is x

Second number is (x + 25)

Third number is 2(x + 25)

[x + (x + 25) + 2(x + 25)]/3 = 85

⇒ [x + x + 25 + 2x + 50]/3 = 85

⇒ (4x + 75)/3 = 85

⇒ 4x + 75 = 255

⇒ 4x = 255 - 75

⇒ 4x = 180

⇒ x = 45

Second number is 70 [i.e 45 + 25]

Third number is 140 [i.e. 2(70)]

∴ Second and third number is 70 and 140