Posted by **Anonymous** on Wednesday, June 27, 2012 at 1:15pm.

Sara tossed a fair coin five times, and Kaleb tossed a fair coin three times. There were five heads and three tails in the eight tosses. What is the probability that either Sara or Kaleb tossed exactly three heads? Express your answer as a common fraction.

- common fraction -
**Count Iblis**, Wednesday, June 27, 2012 at 4:23pm
Probability that Sarah throws exactly 3 heads:

Binomial[5,3] 2^(-5) = 10/32 = 5/16

Probability that Sarah does not throw excatly 3 heads is:

1 - 5/16 = 11/16

Probability that Kaleb throws exactly 3 heads:

1/8

Probability that Kaleb does not throw excatly 3 heads is:

1-1/8 = 7/8

Probability that neither Kaleb nor Sarah throw exactly 3 heads is:

11/16 * 7/8 = 77/128

Probability that either Kaleb or Sarah throw exactly 3 heads is:

1 - 77/128 = 51/128

## Answer this Question

## Related Questions

- math - a fair coin is tossed in the air 4 times. if the coin lands heads up the ...
- math - Seth tossed a fair coin five times and got five heads. The probability ...
- probability - if a fair coin is tossed 4 times, what is the probability of ...
- algebra 2 - A fair coin is tossed 4 times. Given that each of the first 3 tosses...
- Data management - A coin was tossed 1000 times in an experiment to decide ...
- Data Management Help! - A coin was tossed 1000 times in an experiment to decide ...
- Math Problem ( 6th grade math) - Brandon tosses a coin 500 times. The coin lands...
- CALC - A biased coin whose chance of heads is 0.4 is tossed five times in a row...
- Math - Victoria tossed a coin 30 times and got 17 heads. What is the ratio of ...
- math-probability - A student claims that if a fair coin is tossed and comes up ...

More Related Questions