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: if n is a positive integer and n ^ 2 is divisible by 36, then the largest positive integer that must divide n is
Options: a. 6, b. 12, c. 24, d. 36, e. 48

A: a
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Q: Problem: a sum of money at simple interest amounts to rs. 720 after 2 years and to rs. 1020 after a further period of 5 years. the sum is :
Options: a. 400, b. 500, c. 600, d. 700, e. 800

A: c
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Q: Problem: kelly has had 3 pay cuts in her salary in the past 6 months. if the first pay cut was 8 %, the second pay cut was 14 % and the third was 18 %. what will be the percentage decrease, if the salary is decreased in a single shot ?
Options: a. 35.9 %, b. 34.12 %, c. 32.12 %, d. 35.12 %, e. 31.12 %

A:
d
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