
Name: Lindsay
Who is asking: Student
Level: Secondary
Hi,
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]
Hi Lindsay,
 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.
I hope this helps,
Penny
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