How do you calculate cumulative probability? If one tosses a coin 3 times, what are the odds that 1 toss will be "heads"?

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How do you calculate cumulative probability? If one tosses a coin 3 times, what are the odds that 1 toss will be "heads"?

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Answer 1 · 2017-12-02T05:35:59

$3/8$

Explanation:

There are two ways I can think of:

Method 1

In order to have exactly one head in three rows, it means the other two throws are tails. Consider how this could happen:
The 'head could be on the first, second, or third throw.

$P(H,T,T) or P(T,H,T) or P(T,T,H)$

$P(H) =P(T) = 1/2$

$P(H,T,T) or P(T,H,T) or P(T,T,H)$

$= (1/2xx1/2xx1/2)+(1/2xx1/2xx1/2)+(1/2xx1/2xx1/2)$

$= 1/8+1/8+1/8 =3/8$

Method 2

Write down all the $8$ possible outcomes for $3$ throws:

$HHH$

$color(blue)(HT T, HTH, T TH)$

$THH, THT, HHT$

$T T T$

Of the $8$ outcomes there are $color(blue)(3)$ which have one head.

$P("one head") = 3/8$

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How do you calculate cumulative probability? If one tosses a coin 3 times, what are the odds that 1 toss will be "heads"?

1 Answer

Explanation:

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