Question

Roberts father is 4 times as old Robert.After 5 years, father will be three times as old as Robert.Find their present ages

Answer 1

HEYA MATE!

HERE'S YOUR ANSWER!!

Let Robert's age be x.

Then, Robert's father's age will be 4x.

After 5 years,

Robert's age= x+5

Robert's father age= 3x/ 4x+5

According to question,

4x+5 = 3(x+5)

4x+5 = 3x+15

4x-3x = 15-5     (transposing 3x and 5)

1x = 10

x= 10

We've got x = 10

so,

Robert's present age = 10

Robert's father's present age = 4x = 40

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HOPE IT HELPS YOU!!!!!

Answer 2

$\boxed{\boxed{\LARGE\mathsf{10 ; 40}}}$
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Using method of Linear Equation in 2 Variables
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$\underline{\underline{\large\mathfrak{Solution :}}}$

Let the present age of Robert be $\mathbf{x}$

And, the Present age of his father be $\mathbf{y}$

$\underline{\large\mathsf{A.T.Q,}}$

$\mathsf{4x = y}$

$\mathbf{=> 4x - y = 0 -----(1)}$

$\mathsf{3(x+ 5) = y + 5}$

$\mathsf{=> 3x + 15 = y + 5}$

$\mathbf{=> 3x - y + 10 = 0 ----(2)}$
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$\underline{\textbf{Subtracting equation( 1 ) by equation ( 2 ), we get}}$

$\mathsf{x- 10 = 0}$

$=> \boxed{\mathbf{x = 10}}$

$\underline{\textsf{Substituting Value of x in equation ( 1 ), We get,}}$

$\mathsf{=> 4(10) = y}$

$=> \boxed{\mathbf{y = 40}}$
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Hence, present age of Rohan is $\mathbf{10 \: years}$.

And, present age of his father is $\mathbf{40 \: years}$.

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