Multiple choice

If 10 coins are tossed 100 times, then how many times would you expect 7 coins to fall showing heads?

  1. 14

  2. 12

  3. 13

  4. 11
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The probability of getting exactly 7 heads when tossing 10 fair coins once is given by the binomial probability formula, which is 10C7 * (0.5)^10 = 120 / 1024. For 100 trials, the expected frequency is 100 * (120 / 1024), which is approximately 11.72. Rounding to the nearest whole number gives 12.

AI explanation

Using the binomial probability formula, the probability of getting exactly 7 heads in a single toss of 10 coins is 10C7 times (1/2)^7 times (1/2)^3, which equals 120/1024. Multiplying this probability by the 100 times the coins are tossed gives an expected frequency of 11.71875. Rounding this to the nearest whole number gives approximately 12. The result is 12.

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