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: a bag contains 21 toys numbered 1 to 21. a toy is drawn and then another toy is drawn without replacement. find the probability that both toys will show even numbers.
Options: a. 5 / 21, b. 9 / 42, c. 6 / 22, d. 4 / 21, e. 3 / 21

A: b
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Q: Problem: a certain roller coaster has 6 cars, and a passenger is equally likely to ride in any 1 of the 6 cars each time that passenger rides the roller coaster. if a certain passenger is to ride the roller coaster 6 times, what is the probability that the passenger will ride in each of the 6 cars ?
Options: a. 3 / 1944, b. 1 / 96, c. 2 / 96, d. 1 / 1944, e. 1

A: a
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Q: Problem: a producer of tea blends two varieties of tea from two tea gardens one costing rs 18 per kg and another rs 20 per kg in the ratio 5: 3. if he sells the blended variety at rs 25 per kg, then his gain percent is
Options: a. 12 %, b. 33 %, c. 14 %, d. 15 %, e. 16 %

A:
b
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