The annual income of A and B are in the ratio 3: 4 and their annual expenditure are in the ratio 5:7. If each saves 15000 per month find their annual income.

Expert Answers

An illustration of the letter 'A' in a speech bubbles

The annual income of A and B are in the ratio 3 : 4. If the income of A is 3x, the income of B is 4x. Their annual expenditure is in the ratio 5:7, if A's expenditure is 5y, B's expenditure is 7y. Each of them saves 15000 per month.

=> 3x - 5y = 15000 and 4x - 7y = 15000

3x - 5y = 15000

=> y = (3x - 15000)/5

Substituting in 4x - 7y = 15000

=> 4x - 7*(3x - 15000)/5 = 15000

=> 20x - 21x + 105000 = 75000

=> x = 30000

This gives the income of A as 90000 and of B as 120000

Approved by eNotes Editorial Team
Soaring plane image

We’ll help your grades soar

Start your 48-hour free trial and unlock all the summaries, Q&A, and analyses you need to get better grades now.

  • 30,000+ book summaries
  • 20% study tools discount
  • Ad-free content
  • PDF downloads
  • 300,000+ answers
  • 5-star customer support
Start your 48-Hour Free Trial