Given a math problem with context and a question and 5 answer choices, the task is to provide the correct answer choice based on the problem. You must choose one of the given answer choices by letter: a, b, c, d, or e; anything else is invalid.

Q: Problem: at the wholesale store you can buy an 8 - pack of hot dogs for $ 1.55, a 20 - pack for $ 3.05, and a 250 - pack for $ 22.95. what is the greatest number of hot dogs you can buy at this store with $ 205 ?
Options: a. 1,108, b. 2,100, c. 2,140, d. 2,124, e. 2,256

A: c
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Q: Problem: if 20 typists can type 50 letters in 30 minutes, then how many letters will 40 typists working at the same rate complete in 1 hour ?
Options: a. 400, b. 500, c. 350, d. 250, e. 200

A: a
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Q: Problem: if each side of a square is increased by 20 %, find the percentage change in its area ?
Options: a. 40 %, b. 42 %, c. 46 %, d. 44 %, e. 38 %

A:
d
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