The GMAT Sample Math question for the day is from the topic Permutation and Combination.
Ten coins are tossed simultaneously. In how many of the outcomes will the third coin turn up a head?
- 210
- 29
- 3 * 28
- 3 * 29
- None of these
The correct choice is (B) and the correct answer is
29.
When a coin is tossed once, there are two outcomes. It can turn up a head or a tail.
When 10 coins are tossed simultaneously, the total number of outcomes = 2
10
Out of these, if the third coin has to turn up a head, then the number of possibilities for the third coin is only 1 as the outcome is fixed as head.
Therefore, the remaining 9 coins can turn up either a head or a tail = 2
9
eBooks on Permutation Combination & Probability
This ebook with over 110 questions in about 100 pages covers all major concepts in Permutation combination (combinatorics) and Probability. Includes typical GMAT like problems such as "tossing of coins", "rolling of dice" and "selecting cards from a pack of cards" 
This eBook is a practice test comprising 95 questions on Permutation, Combination and Probability. These questions are objective type multiple choice questions. Each question is provided with correct answers and detailed explanations at the end of the test. 
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