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?
- 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 = 210
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 = 29
eBooks on Permutation Combination & Probability