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Airforce Group Y 13 Jul 2021 Shift 1 Memory Based Paper

Option 1 : 45%

Total C.P = Rs. 45000

C.P of (3/5) part = (3/5) × 45000

⇒ Rs. 27000

Remaining part = 1 - (3/5)

⇒ 2/5

C.P of (2/5) part = Rs. (45000 - 27000)

⇒ Rs. 18000

Let required profit % be x%.

By the weighted average method,

Now, (x - 15)/20 = 27000/18000

⇒ (x - 15)/20 = 3/2

⇒ 2(x - 15) = 3 × 20

⇒ 2x - 30 = 60

⇒ 2x = 60 + 30

⇒ 2x = 90

⇒ x = 45

∴ The required profit percentage will be 45%.

Traditional Method:

Given:

The price of the land = Rs. 45000

Loss percentage in selling (3/5) part to him = 5%

Profit percentage earned on the whole process = 15%

Formula Used:

S.P = C.P × {(100 + P%)/100}

S.P = C.P × {(100 - L%)/100}

P = S.P - C.P

Profit percentage = (P/C.P) × 100

Where, S.P = Selling Price

C.P = Cost Price

P = Profit

L = Loss

Calculation:

Total C.P = Rs. 45000

Total S.P = 45000 × {(100 + 15)/100}

⇒ 450 × 115

⇒ Rs. 51750

C.P of (3/5) part = (3/5) × 45000

⇒ Rs. 27000

S.P of (3/5) part = 27000 × {(100 - 5)/100}

⇒ 270 × 95

⇒ Rs. 25650

Remaining part = 1 - (3/5)

⇒ 2/5

C.P of (2/5) part = Rs. (45000 - 27000)

⇒ Rs. 18000

S.P of (2/5) part = Rs. (51750 - 25650)

⇒ Rs. 26100

Required profit = Rs. (26100 - 18000)

⇒ Rs. 8100

Required profit percentage = (8100/18000) × 100

⇒ 810/18

⇒ 45%

∴ The required profit percentage will be 45%.