Who is asking: Student
1)Two trains are 250 miles apart on the same track heading towards eaxh other at 7AM- The first train travels at 55mph, the second at 75mph. At what time would they crash?
2)A cracker box measures 12 by 2 by 18 inches. The company wants to double the amount of crackers, but keep the shapes the same[similar] Find the new length[nearest tenth of an inch]
I hope this helps,
- As the trains move toward each other think of the distance between them. This distance starts at 250 miles and decreases to 0 miles. At what rate is this distance decreasing? How long does it take to decrease to 0?
Suppose that the smallest dimension of the new box is x inches. In the existing box the next largest dimesnion is 6 times the smallest dimension thus, in the new box, the next largest dimension has to be 6 times x. In the existing box the largest dimesnion is 9 times the smallest dimension thus, in the new box, the largest dimension has to be 9 times x. Thus the new box is 6x inches by x inches by 18x inches.
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