The ratio between two natural number is 3:4 , find the smallest number which must be added so that the ratio becomes 4:5 and the sum of the numbers will be 27.
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e. 3
The final ratio will be 4 : 5 and sum will be 27 so,
final numbers will be 4/9 × 27 = 12 and 5/9 × 27 = 15
let initial numbers be 3x and 4x,
And let y be the smallest number which must be added
A/c to ques. (3x + y)/(4x + y) = 12/15 or (12 - y)/(15 - y) = 3/4
⇒ 48 - 4y = 45 - 3y
⇒ 48 - 45 = -3y + 4y
⇒ y = 3