Somehow the answer to B is 24 but I’m not sure how
- Thread starter Vw05
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Dr.Peterson
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You showed your work for part (a) but not for (b). I presume you did the same thing, dividing 8*5*5=200 by 8 to get 25.
The reason for part (c) is to reveal why that's wrong!
Think very specifically about how you'd pack the bars. Which dimension (1, 2, 4) will be parallel to each of the dimensions of the box (8, 5, 5)? How many will fit in each direction? You'll find that, although if you melted the bars and poured them into the box, or broke them in the right way, you could fit 25, but there will be some empty space when you try to fit whole bars. In fact, then you'll have to try to fill that space with more bars.
The reason for part (c) is to reveal why that's wrong!
Think very specifically about how you'd pack the bars. Which dimension (1, 2, 4) will be parallel to each of the dimensions of the box (8, 5, 5)? How many will fit in each direction? You'll find that, although if you melted the bars and poured them into the box, or broke them in the right way, you could fit 25, but there will be some empty space when you try to fit whole bars. In fact, then you'll have to try to fill that space with more bars.
Otis
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Hi Vw05. A short explanation is that only one of the bar's dimensions divides evenly into each of the box dimensions. (In the first question, they all do.)
5÷2 and 5÷4 have remainders. Those remainders lead to unused box space, no matter how the bars are packed.
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