Question

If an investment of Rs.1000 and Rs.100 yield an income of Rs.90 and Rs.20 respectively,
for earning Rs.50 investment of Rs. will be required.
(a) Less than Rs.500
(b)Over Rs.500
(c) Rs.485
(d) Rs.486​

Answer 1

Answer:

Option D is correct.

Step-by-step explanation:

Let x be the part of investment of Rs. 1000 and ( 1 - x ) be the part of investment of Rs. 500.

Total Investment = 1000x + ( 1 - x )100 = 1000x + 100 - 100x = 900x + 100

Total Earning = 90x + ( 1 - x )20 = 90x + 20 - 20x = 70x + 20

According to the Question,

70x + 20 = 50

70x = 50 - 20

70x = 30

x = 30/70

x = 3/7

Now, Total Investment = 900 × 3/7 + 100 = 385.7 +100 = 485.7 ≈ Rs. 486

Therefore, Option D is correct.