# fancy some toast?

• Aug 4th 2009, 11:08 AM
jickjoker
fancy some toast?
A carton contains 12 toasters, 3 of which are defective. If four toasters
are sold at random, find the probability that exactly one will be
defective.?
• Aug 4th 2009, 11:35 AM
Plato
If an urn contains three red balls and nine blue balls and we select four of those balls the probability of getting exactly one red ball is:
$\frac{3\binom{9}{3}}{\binom{12}{4}}$.
• Aug 5th 2009, 10:46 AM
jickjoker
hello tx for your help plato

so would the probability be about 50.9 % ?

just trying to find out if the answer in the book im reading
is correct , so il know the formula to work out these problems in the future

tx

• Aug 6th 2009, 05:53 AM
mr fantastic
Quote:

Originally Posted by jickjoker
hello tx for your help plato

so would the probability be about 50.9 % ?

just trying to find out if the answer in the book im reading
is correct , so il know the formula to work out these problems in the future

tx

Well, if the result Plato gave you is equal to 0.509 (to three decimal places) then I suppose the answer is yes (although I detest probability being expressed as a percentage).