Q8 of 186 Page 4

The ratio of incomes of two persons is 9 : 7 and the ratio of their expenditure is 4 : 3. If each of them manages to save Rs. 2000 per month, find their monthly incomes.

Given ratio of incomes = 9:7

And the ratio of their expenditures = 4:3


Saving of each person = Rs. 2000


Let incomes of two persons = 9x and 7x


And their expenditures = 4y and 3y


According to the question,


9x – 4y = 2000


⇒9x – 4y – 2000 = 0 …(i)


7x – 3y = 2000


⇒7x – 3y – 2000 = 0 …(ii)


By cross - multiplication method, we have





On taking I and III ratios, we get



⇒ x = 2000


On taking II and III ratios, we get



⇒ y = 4000


Hence, the monthly incomes of two persons are 9(2000) = Rs18000 and 7(2000) = Rs14000


More from this chapter

All 186 →
6

If the cost of 2 pencils and 3 erasers is Rs. 9 and the cost of 4 pencils and 6 erasers is Rs. 18. Find the cost of each pencil and each eraser.

 7

The paths traced by the wheels of two trains are given by equations x + 2y – 4 = 0 and 2x + 4y – 12 = 0. Will the paths cross each other?

 9

The sum of two - digits number and the number obtained by reversing the digits is 66. If the digits of the number differ by 2, find the number. How many such numbers are there?

 10

If we add 1 to the numerator and subtract 1 from the denominator, a fraction reduces to 1. It becomes 1/2 if we add 1 to the denominator. What is the fraction?