Browse by Stream
QnA
Home
QnA
Go To Your Study Dashboard

Get Answers to all your Questions

header-bg qa
  • Home
  • NCERT
  • Form the pair of linear equations for the following problems and find their solution by substitution method. (vi) Five years hence, the age 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

Q3.    Form the pair of linear equations for the following problems and find their solution by substitution method.

                (vi) Five years hence, the age 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 (1)

best_answer

Let x be the age of Jacob and y be the age of Jacob's son,

Now, According to the question 

x+5=3(y+5)

\Rightarrow x+5=3y+15

\Rightarrow x-3y=10..........(1)

Also,

x-5=7(y-5)

\Rightarrow x-5=7y-35

\Rightarrow x-7y=-30.........(2)

Now,

From (1) we have,

x=10+3y...........(3)

Substituting this value of x in (2) 

10+3y-7y=-30

\Rightarrow -4y=-30-10

\Rightarrow 4y=40

\Rightarrow y=10

Substituting this value of y in (3),

x=10+3y=10+3(10)=10+30=40

Hence, Present age of Jacob is 40 years and the present age of Jacob's son is 10 years.

 

Posted by

Pankaj Sanodiya

View full answer

Similar Questions

Trending Articles/News

anam-khan

CBSE Class 10 board exams from February 15 to March 18; download date sheet 2025 PDF
anam-khan

CBSE Date Sheet 2025 Live: CBSE Class 10, 12 board exam timetable soon at cbse.gov.in; practical dates
anam-khan

CBSE Date Sheet 2025 Live: CBSE to announce Class 10, 12 board exam dates soon at cbse.gov.in; sample paper

Latest Question