Multiple choice

A watch was sold at a profit of 15%. If its cost had been 5% less and it had been sold for Rs 21 less, then the profit would have been 10%. Find the cost price of the watch.

  1. Rs. 100

  2. Rs. 200

  3. Rs. 168

  4. Rs. 225

  5. None of these
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Let CP = x. Original SP = 1.15x (15% profit). If CP were 5% less (0.95x) and sold for Rs 21 less (1.15x - 21), profit = 10%. So (1.15x - 21) / 0.95x = 1.10. Solving: 1.15x - 21 = 1.045x, so 0.105x = 21, x = 200. Verify: CP=200, SP=230 (15% profit). If CP=190 and SP=209, profit = 19/190 = 10%. Correct.

Keep practicing — related questions