Can you explain the answer of this question below:Four years ago, the ...
4 years ago
A-4:B-4=13:9
(A-4)/(B-4)=13/9
solving the equation
9A-13B=-16
similarly 8 years after
equation
3A-4B=8
solving both equation we get the value of A,B as 56,40
difference of ages=16 years.
Can you explain the answer of this question below:Four years ago, the ...
Given information:
Four years ago, the ratio of the ages of A and B was 13:9.
Eight years hence, the ratio of their ages would be 4:3.
To find:
The difference in their present ages.
Solution:
Let's assume the present age of A is 13x and the present age of B is 9x.
Four years ago, A's age was (13x - 4) and B's age was (9x - 4).
According to the given ratio, we can write the equation:
(13x - 4) / (9x - 4) = 13 / 9
Cross-multiplying, we get:
117x - 52 = 117x - 52
This equation shows that the ratio of their ages has remained the same over the past four years.
Now, let's consider their ages eight years hence.
A's age after eight years would be (13x + 8) and B's age after eight years would be (9x + 8).
According to the given ratio, we can write the equation:
(13x + 8) / (9x + 8) = 4 / 3
Cross-multiplying, we get:
39x + 24 = 36x + 32
Simplifying the equation, we get:
3x = 8
Dividing both sides by 3, we find:
x = 8/3
Therefore, A's present age is:
13x = 13 * (8/3) = 104/3
And B's present age is:
9x = 9 * (8/3) = 72/3
The difference in their present ages is:
(104/3) - (72/3) = 32/3 = 10 2/3 = 16 years (approximately)
Hence, the correct answer is C: 16 years.