Question

A is twice old as B. Five years ago A was 3 times as old as B. Find their presentages

Answer 1

Answer:

A = 20 years,

B = 10 years.

Step-by-step explanation:

As per the question,

Let us say the age of B = x

So,

Age of A = 2x

Age of A, 5 years ago = 2x - 5

Age of B, 5 years ago = x - 5

So, from the given question we can say that,

(2x-5)= 3(x - 5)

2x5= 3x - 15

x = 15-510

x = 10 years.

Therefore, we can see that,

Age of B = 10 years.

and,

Age of A = 20 years.

Therefore, the present age of A and B are 20 and 10 years respectively.

Answer 2

❍ Let's consider that, the age of B be x and according to the question, age of A be 2x.

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– Five years ago:

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• A's age = (2x - 5)
• B's age = (x - 5)

⠀⠀⠀⠀⠀━━━━━━━━━━━━━━━━━━━⠀⠀⠀⠀⠀⠀⠀⠀

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$\underline{\bigstar\;\boldsymbol{According\;to\;the\;Question\;:}}$

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• Five years ago, A was three times as old as B.

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Therefore,

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$\begin{gathered}:\implies\sf{2x-5=3(x-5)}\\\\\\\\:\implies\sf{2x-5=3x-15}\\\\\\\\:\implies\sf{2x-3x=-15+5}\\\\\\\\:\implies\sf{\cancel{-}\;x=\cancel{-}\;10}\\\\\\\\:\implies\underline{\boxed{\frak{\pink{x=10}}}}\;\bigstar\end{gathered}$

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Hence,

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• Present age of A = 2x, 2(10) = 20 years
• Present age of B = x = 10 years

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$\therefore\;{\underline{\sf{Hence,\;their\;ages\;are\;{\textsf{\textbf{20\;years}}}\;\&\;{\textsf{\textbf{10\;years}}}\;respectively.}}}$⠀⠀⠀