Walking across campus, a student interviewed a group of students. 25% of the students took a finance class last semester, 51% took a marketing class last semester, and 40% took neither a finance nor a marketing class last semester. What percent of the students in the group took both a finance and a marketing class?
Options:
(A) 60%
(B) 50%
(C) 25%
(D) 16%
(E) 10%
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{Total} = {finance} + {marketing} - {both} + {neither}
100 = 25 + 51 - {both} + 40
{both} = 16%. So the answer is: (D).
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For a particular American football game, the probability of a team's quarterback throwing a completed pass on each throw is 3/10. What is the least number of times that the quarterback should throw the ball that will increase the probability of getting a completed pass at least once to more than 50%.
Options:
(A) 10
(B) 5
(C) 2
(D) 3
(E) 1
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Rule of Subtraction: P(A) = 1 - P(A')
Rule of Multiplication: P(A B) = P(A) P(B)
The probability that the quarterback throws a completed pass at least once in 2 throws is 1- (7/10)^2 = 1 - 49/100 = 51/100 > 50% So the answer is: (C).
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Find the expenditure on digging a well 14m deep and of 3m diameter at Rs.15 per cubic meter?
Options:
(A) Rs.1185
(B) Rs.1285
(C) Rs.1385
(D) Rs.1485
(E) Rs.1495
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22/7 * 14 * 3/2 * 3/2 = 99 m2
99 * 15 = 1485 So the answer is: (D).
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