Question

A shop wants to sell a certain quantity (in kg) of grains. It sells half the quantity and an additional 3 kg of these grains to the first customer. Then, it sells half of the remaining quantity and an additional 3 kg of these grains to the second customer. Finally, when the shop sells half of the remaining quantity and an additional 3 kg of these grains to the third customer, there are no grains left. The initial quantity, in kg, of grains is

Accepted Answer

D. Working backwards: - Before 3rd customer: $\frac{x_3}{2} - 3 = 0 \implies x_3 = 6$ kg. - Before 2nd customer: $\frac{x_2}{2} - 3 = 6 \implies \frac{x_2}{2} = 9 \implies x_2 = 18$ kg. - Before 1st customer: $\frac{x_1}{2} - 3 = 18 \implies \frac{x_1}{2} = 21 \implies x_1 = 42$ kg.

Grain Sales Sequence

Explanation

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