Subject: General Aptitude · Chapter: Ratio and Proportion · Exam: · Marks: · Difficulty:
The ratio of incomes of two persons is 5 : 3 and that of their expenditures is 9 : 5. If they save ₹ 2600 and ₹ 1800 respectively, their incomes are
(a)₹ 9000, ₹ 5400
(b)₹ 10000, ₹ 6000
(c)₹ 6000, ₹ 3600
(d)₹ 8000, ₹ 4800
Answer
Answer (as printed): D
Explanation
Let the incomes of the two persons be $5 x$ and $3 x$ and their expenditures be $9 y$ and $5 y$ respectively. Then, $5 x-9 y=2600$ $$\text { and } \quad 3 x-5 y=1800$$ Multiplying (i) by 3 and (ii) by 5, we get : $$15 x-27 y=7800 \text { and } \quad 15 x-25 y=9000$$ Subtracting (iii) from (iv), we get : $2 y=1200$ or $y=600$. Putting $y=600$ in (i), we get : $5 x=8000$ or $x=1600$. ∴ Their incomes are ₹ $(5 \times 1600)$ and ₹ $(3 \times 1600)$ i.e., ₹ 8000 and ₹ 4800 respectively.
Explanation as extracted from the printed page; notation may be imperfect.