2019 AMC 10A Problems/Problem 10

Revision as of 18:58, 9 February 2019 by Archiyaa (talk | contribs) (Solution)

Problem

A rectangular floor that is $10$ feet wide and $17$ feet long is tiled with $170$ one-foot square tiles. A bug walks from one corner to the opposite corner in a straight line. Including the first and the last tile, how many tiles does the bug visit?

$\textbf{(A) } 17 \qquad\textbf{(B) } 25 \qquad\textbf{(C) } 26 \qquad\textbf{(D) } 27 \qquad\textbf{(E) } 28$

Solution

Because this is a $10$ by $17$ grid, the number of tiles that the bug visits is $10+17-1=26\implies C$.

Note: You will find that the general formula for this is $a+b-lcm(a,b)$

See Also

2019 AMC 10A (ProblemsAnswer KeyResources)
Preceded by
Problem 9
Followed by
Problem 11
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 AMC 10 Problems and Solutions

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