Question

Q - five years hence, the age of Jacob will be three time that of his son . five years ago Jacob's age was seven times that of his son . what are their present ages .
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Answer 1

Step-by-step explanation:

let x present age of jacob and y be the age of his son

x+5=3(y+5)

x _ 5 =7(y_5)

2x =3y+15+7y_35

2x=10y_20

x=5y_10

5y_5=3y+15

2y=20

y=10

x=5×10_10

x= 40

Answer 2

Answer:

j=Jacob

s=son

—5 years ratio j : s = 7:1

Ratio difference 7–1 =6

+5 years ratio 3:1

Ratio difference 3–1 =2

Make ratio difference same so multiply +5 ratio with 3 then ratio will be 9:3

Difference between —5 and +5 years is 10 years

Absorb ratios 7:1. And 9:3 and there difference is also equal

Then 9–7 = 2

Or 3–1 = 2

Then this 2 equals to 10 years

i.e means 1 part is 5 years

Take any one of above equation

—5 years ratio is 7:1 multiply with 5

—5 years ages are Jacob 35 and son 5

Now there ages are 40 and 10