vi) Five years hence, the ago of Jacob will be three times that of his son .
Five years ago, Jacob's age was seven times that of his son .What are their present ages
Answers
Jacob's age is 40 years and his son's age is 10 years.
Answer:
Present age of Jacob is 40 years and his son is 10 years old
Step-by-step explanation:
Given :
The age of Jacob will be three times that of his son
To find:
Their present ages
Solution :
Consider =
- Present age of Jacob be be 'x'
- Present age of his son be be 'y'
Ages 5 years back -
- Jacob’s = x + 5
- His son = y + 5
★ According to the Question -
The age of Jacob will be three times that of his son
⇒ x + 5 = 3(y + 5)
⇒ x = 3y + 15 - 5 (Add 5 to both sides)
⇒ x = 3y + 10 … (Eq. I)
Scenario 5 years ago -
⇒ x - 5 = 7(y - 5)
Place the value of x from equation I
⇒ 3y + 10 - 5 = 7y - 35
⇒ 3y + 5 = 7y – 35
⇒ 3y - 7y = - 35 - 5
⇒ -4y = - 40
⇒ y = - 40/-4
⇒ y = 10
Place the value of y
⇒ x = 3 × 10 + 10
⇒ x = 40
Present age of Jacob is 40 years and his son is 10 years old