There are 18 number-tiles in a jar, each marked with a different number from 1-18. If you pull out one tile at random, what is the probability that the number you pull will be an even number or a prime number?
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A0.944
B0.722
C0.889
First, let's determine the total number of favorable outcomes.
Even numbers between 1-18 are: 2, 4, 6, 8, 10, 12, 14, 16, 18 (9 numbers)
Prime numbers between 1-18 are: 2, 3, 5, 7, 11, 13, 17 (7 numbers)
However, we need to be careful not to double count the number 2, which is both an even number and a prime number. Therefore, the total number of favorable outcomes is 9 + 7 - 1 = 15.
The total number of possible outcomes is 18 (since there are 18 different number-tiles).
Therefore, the probability of pulling out an even number or a prime number is 15/18 = 0.833.
Therefore, the correct answer is not listed, but out of the given options, the closest answer is A) 0.944.