Question

8. Three numbers are in the ratio 2 : p : 5. The third number is greater than the first one by 21. Find the value of p if their sum is70.
(A) 8 (B) 6 (C) 3 (D) 11​

Answer 1

Given -

• Three numbers are in the ratio 2: p : 5
• The third number is greater than the first one by 21
• Sum of the three numbers is 70

To find -

• The value of p

Solution -

Let ,

the first number be 2x

the second number be px

the third number be 5x

According to the question,

$5x = 2x + 21$

$5x - 2x = 21$

$3x = 21$

$x = \frac{21}{3}$

$x = 7$

Sum of three numbers =70

$2x + px + 5x = 70$

$7x + px = 70$

$7 \times 7 + 7p = 70$

$49 + 7p = 70$

$7p = 70 - 49$

$7p = 21$

$p = \frac{21}{7}$

$p = 3$

Therefore the value of p is 3