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A refrigerator is 8 inches long , 4 inches wide and 5 inches high.How many ice cubes will it hold if each cube is 2 inches on the edge.

According to me its 20 because volume of Fridge = 160 and volume of cube=8 so 160/8 = 20 However the books says the answer is 24. Am i missing something or is this a misprint ?

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    @Rajeshwar: Your reasoning is only partly right. By volume considerations, the answer is clearly $\le 20$. In fact it is less than $20$, because of the $5$ inch part. We can certainly fit in $16$. Perhaps one can fit in one more by using a strange packing. Certainly one can if we replace $5$ by $5.9$.2012-06-28

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You can get only $\frac{8}{2}$ times $\frac{4}{2}$ times the floor value of $\frac{5}{2}$, which is $2$ inside. This means a total of $16$ ice cubes.

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    I $a$gree 16 is the right answer, but so far the reasoning is not completely convincing. The lower bound 20 as computed by the OP is correct and convincing.2019-05-10
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We can fill 20 ice cubes with respect to deep and wide, if we assume that compartment has 2 floors. If ice cubes are sliced then we can fill 5cubes with respect to high 5 inches which has 1inch unfilled.then totally we can fill 25cubes. This answer might be our assumption