2008 AMC 12B Problems/Problem 10
Contents
[hide]Problem
Bricklayer Brenda would take hours to build a chimney alone, and bricklayer Brandon would take hours to build it alone. When they work together they talk a lot, and their combined output is decreased by bricks per hour. Working together, they build the chimney in hours. How many bricks are in the chimney?
Solution
Let be the number of bricks in the chimney.
Without talking, Brenda and Brandon lay and bricks per hour respectively, so together they lay per hour together.
Since they finish the chimney in hours, . Thus, .
Video Solution
See Also
2008 AMC 12B (Problems • Answer Key • Resources) | |
Preceded by Problem 9 |
Followed by Problem 11 |
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All AMC 12 Problems and Solutions |
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