Question

Thus, the publisher will break even when 25.600 books are
12.5
EXERCISE - 4.2
Form a pair of linear equations for each of the following problem
The ratio of incomes of two persons is 9:7 and the ratio of the
each of them manages to save 2000 per month, find their mon​

Answer 1

Let income of first person =9x

Then, income of second person =7x

Let expenditutres of first person =4y

Then, expenditutres of second person =3y

Now, we are given,

9x−4y=2000→(1)

7x−3y=2000→(2)

From (1) and (2),

9x−4y=7x−3y

2x=y

Putting value of y in (1)

9x−4(2x)=2000⇒x=2000 y=20002=1000

So, income of first person in Rs =9x=18000

Then, income of second person in Rs =7x=14000