2005 AMC 8 Problems

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These are equivalent problems, but modified in form but preserving original math idea.

1. Shannon multiplies a number by 2 and gets 64 as her answer. However, she should have divided the number by 2 to get the correct answer. What is the correct answer?

(A) 8 (B) 16 (C) 32 (D) 128 (E) 256

2. Kent bought five notebooks from Pay-More at a cost of 4 dollars each. Pay-More had a 25%-off sale a week later. How much could Kent have saved on the purchase by waiting for the sale?

All numbers are in dollars: (A) 2.50 (C) 7.50 (E) $10.00

3.

4.

5. Matha Cola bottles are sold in six-packs, 12-packs, and 20-packs. What is the fewest number of packs you must buy to get exactly 78 bottles of Matha Cola?

(A) 4 (B) 5 (C) 6 (D) 8 (E) 13

Answers: 1.B 2.C 3.B