Sandeep was given some money by his father. He spent all of it in six shops. In each shop, he spent one rupee more than half of what he had when he entered. How much money did Sandeep receive from his father?
- AOption (a)
126 rupees
- BOption (b)
15 rupees
- COption (c)
31 rupees
- DOption (d)
63 rupees
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Correct answer
126 rupees
Why this answer is correct
Given:
Total shops = 6
Condition: In each shop he spends (½ of what he had + ₹1)
At last he has ₹0 left
Formula used:
If money before entering a shop = M
Money spent = (M ÷ 2 + 1)
Money left = M − (M ÷ 2 + 1) = (M ÷ 2 − 1)
We work backward from last shop (final = 0)
Calculations:
After shop 6 = 0
⇒ Before shop 6 = (0 + 1) × 2 = 2
⇒ Before shop 5 = (2 + 1) × 2 = 6
⇒ Before shop 4 = (6 + 1) × 2 = 14
⇒ Before shop 3 = (14 + 1) × 2 = 30
⇒ Before shop 2 = (30 + 1) × 2 = 62
⇒ Before shop 1 = (62 + 1) × 2 = 126
∴ Sandeep received ₹126 from his father.