2012 AMC 8 Problem 13
Attempt Problem 13 of the 2012 AMC 8 below, then check your answer against the video solution and professionally curated solution from LIVE by Po-Shen Loh. You can also try the full timed exam, view all 2012 AMC 8 solutions, or check the answer key.
All problems are used with official legal permission of the Mathematical Association of America (MAA).
13.
Jamar bought some pencils costing more than a penny each at the school bookstore and paid Sharona bought some of the same pencils and paid How many more pencils did Sharona buy than Jamar?
Answer: C
Small hint:
The pencil price in cents divides both and .
Big hint:
Use the greatest common divisor of and .
Video solution:
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Written solution:
Let be the price of one pencil in cents. Then divides both and , and .
Since and , the greatest common divisor is . Thus each pencil costs cents.
Sharona paid cents more, so she bought more pencils. Thus, the answer is C .
Problem 13 in other years
- 1985 AMC 8
- 1986 AMC 8
- 1987 AMC 8
- 1988 AMC 8
- 1989 AMC 8
- 1990 AMC 8
- 1991 AMC 8
- 1992 AMC 8
- 1993 AMC 8
- 1994 AMC 8
- 1995 AMC 8
- 1996 AMC 8
- 1997 AMC 8
- 1998 AMC 8
- 1999 AMC 8
- 2000 AMC 8
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