2007 AMC 8 Problems/Problem 4

Problem

A haunted house has six windows. In how many ways can Georgie the Ghost enter the house by one window and leave by a different window?

$\mathrm{(A)}\ 12 \qquad\mathrm{(B)}\ 15 \qquad\mathrm{(C)}\ 18 \qquad\mathrm{(D)}\ 30 \qquad\mathrm{(E)}\ 36$

Solution

Georgie can enter the haunted house through any of the six windows. Then, he can leave through any of the remaining five windows.

So, Georgie has a total of $6 \cdot 5$ ways he can enter the house by one window and leave by a different window.

Therefore, we have $\boxed{\textbf{(D)}\ 30}$ ways.

Video Solution by SpreadTheMathLove

 2007 AMC 8 (Problems • Answer Key • Resources) Preceded byProblem 3 Followed byProblem 5 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 All AJHSME/AMC 8 Problems and Solutions

The problems on this page are copyrighted by the Mathematical Association of America's American Mathematics Competitions.