The ratio of 2 numbers is 7 : 4, When 28 is added to the smaller number new ratio becomes 7 : 8. What is the minimum number to be added to the current smaller number so that ratio becomes 3 : 2?
The ratio of 2 numbers is 7 : 4, When 28 is added to the smaller number new ratio becomes 7 : 8. What is the minimum number to be added to the current smaller number so that ratio becomes 3 : 2? Correct Answer 35
Let first number be 7x and second number be 4x
When 28 is added in the smaller number then ratio becomes 7 : 8
So, 7x/(4x + 28) = 7/8
⇒ 56x = 28x + 28 × 7
⇒ 28x = 28 × 7
⇒ x = 7
So, first number is 7 × 7 = 49 and second number is 4 × 7 = 28
Now, new first number = 49 and new second number = 28 + 28 = 56
Again, from question let a be added to current smallest number then ratio becomes 3 : 2
So, (49 + a) /56 = 3/2
⇒ 98 + 2a = 168
⇒ 2a = 168 – 98 = 70
⇒ a = 35
∴ Minimum number = 35
মোঃ আরিফুল ইসলাম
Feb 20, 2025