Question

c) lam three times as old as my son. Five years later, I shall be two-and-a-half
times as old as my son. What is my age?
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Answer 1

Step-by-step explanation:

Given: My age is three times as old as my son.

❍ Let my son's age be x years. Then, my age be 3x years.

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

Five years later, I shall be two-and-a-half times as old as my son.

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After five years,

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Son's age = (x + 5)

My age = (3x + 5)

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Therefore,

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$:\implies\sf 3x + 5 = 2\dfrac{1}{2} (x + 5) \\\\\\:\implies\sf 3x + 5 = \dfrac{5}{2} (x + 5) \\\\\\:\implies\sf 2(3x + 5) = 5(x + 5)\\\\\\:\implies\sf 6x + 10 = 5x + 25\\\\\\:\implies\sf 6x - 5x = 25 - 10\\\\\\:\implies{\underline{\boxed{\frak{\pink{x = 15}}}}}\:\bigstar$

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Hence, present ages now:

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Son's age, x = 15 years.

My age, 3x = 3(15) = 45 years.

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$\therefore\:{\underline{\sf{Hence, \ my \ present \ age \ is \ \bf{45 \ years}.}}}$⠀

Answer 2

Answer:

Our first equation will be:

3S = D (because 3 times the sons age is equal to the dads age)

Our second equation we need to add 5 years to both the dads and sons age so it will be:

(S+5)2.5 = D + 5

Now we can substitute the first d into the second equation or s.

So we get:

(S+5)2.5 = 3S + 5

2.5S+12.5 = 3S + 5

-.5S = -7.5

S = 15

So the sons age is 15 and the dads age is 45 (3 times the sons age) . Five years later the son is 20 and the dad is 50 (2.5 the sons age).

Step-by-step explanation:

$Hope \: it \: helpfull...!!$