Question

2. The average of three numbers is
40. The first number is twice the
second and the second one is
thrice the third number. The dif-
ference between the largest and
the smallest numbers is
(1) 30
(2) 36
(3) 46
(4) 60​

Answer 1

here's the correct solution ⬇️

Correct Option: D

Let the third number be p.

∴ Second number = 3p

First number = 6p

∴

6p + 3p + p

= 40

3

⇒ 10p = 120 ⇒ p = 12

∴ Required difference = 6p – p = 5p = 5 × 12 = 60

Second method to solve this question with the help of given formulas :

Here, a = 2, b = 3, X = 40

Largest Number = First Number =

3ab

× X

1 + b + ab

Largest Number =

3 × 2 × 2

× 40

1 + 3 + 2 × 2

Largest Number =

18

× 40 = 72

10

Smallest Number = Third Number =

3

× X

1 + b + ab

Smallest Number =

3

× 40

1 + 3 + 2 × 3

Smallest Number =

3

× 40 = 12

10

Difference = 72 – 12 = 60

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