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2007 AMC 12B Problems/Problem 6

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Problem

Triangle ABC has side lengths AB = 5, BC = 6, and AC = 7. Two bugs start simultaneously from A and crawl along the sides of the triangle in opposite directions at the same speed. They meet at point D. What is BD?

\mathrm {(A)}\ 1 \qquad \mathrm {(B)}\ 2 \qquad \mathrm {(C)}\ 3 \qquad \mathrm {(D)}\ 4 \qquad \mathrm {(E)}\ 5

Solution

Image:2007_12B_AMC-6.png

One bug goes to B. The path that he takes is \dfrac{5+6+7}{2}=9 units long. The length of BD is 9-AB=9-5=4 \Rightarrow \mathrm {(D)}

See also

2007 AMC 12B (ProblemsResources)
Preceded by
Problem 5
Followed by
Problem 7
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
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