单选题Three fair coins are tossed at the same time. What is the probability that all three coins will come up heads or all will come up tails?A1/8B1/6C1/4D1/3E3/8
单选题
Three fair coins are tossed at the same time. What is the probability that all three coins will come up heads or all will come up tails?
A
1/8
B
1/6
C
1/4
D
1/3
E
3/8
参考解析
解析：
If three fair coins are tossed at the same time, the probability that all three will come up heads is (1/2)×(1/2)×(1/2) or 1/8. probability that all three coins will come up tails is also (1/2) × (1/2) × (1/2) or 1/8. Hence, the probability that all three coins will come up heads or all will come up tails is (1/8)+(1/8) or 1/4.
If three fair coins are tossed at the same time, the probability that all three will come up heads is (1/2)×(1/2)×(1/2) or 1/8. probability that all three coins will come up tails is also (1/2) × (1/2) × (1/2) or 1/8. Hence, the probability that all three coins will come up heads or all will come up tails is (1/8)+(1/8) or 1/4.
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