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Popular Word Problems >

Three coins are tossed, what is the probability of getting: two heads or two tails

Solution

T h ree co in s a re t osse d, w ha t i s t h e p ro babi l i t y o f g e tt in g : tw o h e a d s or tw o t ai l s

Solution

\frac{3}{4}

+1

Decimal

0.75

Solution steps

Find the probability of getting: 2 heads:

\frac{3}{8}

Find the probability of 2 tails:

\frac{3}{8}

Since the events are disjoint, Use the formula

P (X_{1} \lor X_{2} \lor \dots \lor X_{k}) = P (X_{1}) + P (X_{2}) + \dots + P (X_{k})

= \frac{3}{8} + \frac{3}{8}

\frac{3}{8} + \frac{3}{8} = \frac{3}{4}

= \frac{3}{4}

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