Question

five years hence the age of jacob will be three times that of son. five years ago jacob s age was seven times that of his son. what are thier present ages

Answer 1

$hi$
Let son's age be x.

Son's age after 5 years.
x + 5

So,
According to given condition ,
Jacobs age = 3(x+5) = 3x+15

His present age = 3x +15 - 5
= 3x+10 ....................... (1)

Five years ago....

Son's age = x - 5
According to the given condition,

Jacobs age = 7(x - 5)
Jacobs age = 7x - 35

His present age = 7x - 35 + 5 =
7x - 30 . . . . . . . .. . . . . . (2)

$from(1) \: and \: (2)$

$3x + 10 = 7x - 30$

$10 + 30 = 7x - 3x$

$40 = 4x$

$x = \frac{40}{4}$

$x = 10$

So,
His sons present age is 10years.

Present age of Jacob=
3x + 10 ...............................from(1)
3(10)+10 = 30 + 10 = 40years.
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Final Answer :
The present ages of Jacob and Son are 40years and 10years.
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$hope \: this \: helps.....$

Answer 2

Answer:

Step-by-step explanation:

Given :-

The age of Jacob will be three times that of his son.

Solution :-

Let the present age of Jacob be be x year                  

And the present Age of his son be be y year    

             

Five years Ago

Jacob’s age will be = x + 5 year                  

Age of his son will be = y + 5 year                  

According to the Question,

⇒ x + 5 = 3(y + 5)                  

Adding 5 to both side,                  

⇒ x = 3y + 15 - 5                  

⇒ x = 3y + 10 … (i)                  

Five years ago,                  

Jacob’s age= x - 5 year                  

His son’s age = y - 5 year                  

Jacob’s age was seven times that of his son                  

⇒ x - 5 = 7(y - 5)                  

Putting the value of x from equation (i) we get                  

⇒ 3y + 10 - 5 = 7y - 35                  

⇒ 3y + 5 = 7y – 35                  

⇒ 3y - 7y = - 35 - 5                  

⇒ -4y = - 40                  

⇒ y = - 40/-4                  

⇒ y = 10 year                  

Putting the value of y in equation we get                  

⇒ x = 3 × 10 + 10                  

⇒ x = 40 years                  

Present age of Jacob = 40 years,

Present age of his son = 10 years.