A coin is thrown 3 times. What is the probability that atleast one head is obtained?
A
\(\frac {7}{8}\)
B
\(\frac {3}{8}\)
C
None the above
D
\(\frac {1}{8}\)
Verified Correct Answer: A.
Step-by-Step Mathematical Solution
Sample space = {HHH, HHT, HTH, THH, TTH, THT, HTT, TTT}
Total number of possible outcomes = 2 x 2 x 2 = 8
favourable number of outcomes = 7
∴Pr(at least one head) = \(\frac {7}{8}\)
Source: WAEC / JAMB / NECO Classroom Archive (Record #67272)