Question

Three years ago A's age was double of B's age. Seven years hence, the sum of their ages will be 83 years.Find the present age of each.
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Answer 1

Answer:

let present age of A be x and of B be y

so according to the question

x - 3 = 2(y - 3) => 2y - x = 3 _____1

also

(x + 7) + (y + 7) = 83 => x + y = 69_____2

adding 1 and 2

we get 3y = 72 => y = 24

substituting y in 2 we get x = 45

Answer 2

Solution

Given That :-

• Three years ago A's age was double of B's age.
• Seven years hence, the sum of their ages will be 83 years

Find :-

• Present age of A & B

Explanation

Let,

• Age of " A " = x years
• Age of " B " = y years

A/C to question,

Case(1).

(Three years ago A's age was double of B's age.)

==> (x-3) = 2 * (y-3)

==> x - 2y = -6 + 3

==> x - 2y = -3 -------------(1)

Case(2).

(Seven years hence, the sum of their ages will be 83 years )

==> (x+7)+(y+7) = 83

==> x + y = 83 - 14

==> x + y = 69 ------------(2)

Subtract equ.(1) & equ(2)

==> -2y - y = -3 - 69

==> -3y = -72

==> y = -72/(-3)

==> y = 24

Keep value of y in equ(2)

==> x + 24 = 69

==> x = 69 - 24

==> x = 45

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Hence

• present Age of " A " will be (x) = 45 years
• present Age of " B " will be (y) = 24 years

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