Question

On tossing three coins simultaneously, find the probability of getting at least one head and tail.

• A. 1/4
• B. 1/2
• C. 3/4
• D. 2/3

Answer 1

The correct option is C

3/4

Given, a coin is tossed 3 times.

Total possible outcomes = {HHH, HHT, HTT, HTH, THH, TTH, THT, TTT} (where H = Heads, T= Tails)

= 8

Number of favourable outcomes (getting at least one head and tail) = {HHT, HTT, HTH, THH, TTH, THT}

= 6

Out of 8 possible outcomes, there are 6 favourable outcomes.

We have,

Probability of an event, P(E) = $\frac{\text{number of favourable outcomes}}{\text{total number of outcomes}}$

$\Rightarrow$ P (getting at least one head and tail) = $\frac{6}{8}$

= $\frac{3}{4}$

Therefore, the probability of getting at least one head and a tail is $\frac{3}{4}$.