A wholesaler marks up the price of a microwave oven by 60% above its cost price. He gives a 15% trade discount to a retailer. The retailer, in turn, marks up the price by 25% above his purchase price and offers a 10% festival discount to the customer. If the customer finally pays ₹14,490 for the microwave, what is the original approximate cost price of the oven to the wholesaler?

Correct — A. Turn every step into a multiplier on the wholesaler's cost C.

Mark-up 60%: C × 1.60 = 1.6C
Trade discount 15%: 1.6C × 0.85 = 1.36C (retailer's purchase price)
Mark-up 25%: 1.36C × 1.25 = 1.7C
Festival discount 10%: 1.7C × 0.90 = 1.53C

Customer pays 1.53C = 14,490
C = 14,490 ÷ 1.53 = 9,470.59 ≈ ₹9,471 → option (a).

Why the others are wrong

• (b)
  ₹9,500 — ₹9,500 is a coarser rounding, about ₹29 off the true 9,470.59. Run forward, 9,500 × 1.53 = ₹14,535, which is ₹45 more than the customer paid.
• (c)
  ₹10,000 — 10,000 × 1.53 = ₹15,300, which is ₹810 above the ₹14,490 the customer paid.
• (d)
  ₹10,500 — 10,500 × 1.53 = ₹16,065, far above ₹14,490. That cost would need a net multiplier of about 1.38 across the four steps, not 1.53.

Successive mark-ups and discounts multiply; they never add. Each rise of x% is a factor (1 + x⁄100), each discount of y% is (1 − y⁄100), and each applies to the price left by the step before.

The four factors collapse into one: 1.6 × 0.85 × 1.25 × 0.9 = 1.53. Divide the final price by it to get the cost.

Adding the percentages instead, 60 − 15 + 25 − 10 = 60%, gives a factor of 1.6 and a cost of ₹9,056.25, which is not offered.

Key facts

• Net factor = 1.6 × 0.85 × 1.25 × 0.9 = 1.53, a 53% rise on the wholesaler's cost.
• The retailer buys at 1.36C and sells at 1.53C, a profit of 12.5% on his own purchase.
• C = ₹14,490 ÷ 1.53 ≈ ₹9,470.59.

Common traps

• Adding the four percentages to a net 60% and dividing ₹14,490 by 1.6.
• Taking the 10% festival discount on the wholesaler's marked price rather than on the retailer's.

No directly related past PYQ was found.