Question

five years hence the age of Jacob will be thee time that of his son five years ago Jacob, s age was seven that of his son. what are their present ages.​

Answer 1

Answer:

here is ur answer

hope it helps

gud night

Answer 2

GIVEN :-

• Five years hence the age of Jacob will be thee time that of his son.
• Five years ago Jacob's age was seven that of his son.

TO FIND :-

• Present ages of Jacob and his son.

SOLUTION :-

Let present age of Jacob be 'x' and Jacob's son be 'y'.

CASE 1 :-

♦ Five years hence the age of Jacob will be thee time that of his son.

Five years hence ,

• Age of Jacob → (x + 5)yrs
• Age of Jacob's son → (y + 5)yrs

So,

x + 5 = 3(y + 5)

x + 5 = 3y + 15

x - 3y = 15 - 5

x - 3y = 10 -------(1)

CASE 2 :-

♦ Five years ago Jacob's age was seven that of his son.

Five years ago ,

• Jacob's age → (x - 5) yrs
• Jacob's son's age → (y - 5) yrs

So,

x - 5 = 7(y - 5)

x - 5 = 7y - 35

x - 7y = -35 + 5

x - 7y = -30 --------(2)

___________________

Now , subtracting equation (2) by equation (1),

→ x - 3y - (x - 7y) = 10 - (-30)

→ x - 3y - x + 7y = 10 + 30

→ 4y = 40

→ y = 40/4

→ y = 10

Substituting value of y in equation (2),

→ x - 7(10) = -30

→ x - 70 = -30

→ x = -30 + 70

→ x = 40

Hence , age of Jacob is 40years and age of his son is 10yrs.