document.write( "Question 1194452: In many situations, the normal distribution can be used to approximate the binomial distribution.
\n" ); document.write( "a)Explain the conditions in which this can be done, and explain why we might take advantage of this property. 
\n" ); document.write( "

Algebra.Com's Answer #826656 by Boreal(15235)\"\" \"About 
You can put this solution on YOUR website!
If there are two outcomes with constant probability
\n" ); document.write( "if np and n(1-p) are > 5 (some use 10)
\n" ); document.write( "Do this where large factorials might occur and cannot be calculated.
\n" ); document.write( "A batter is hitting 0.400. In the next 200 at bats, what is the chance of his getting 90 or more hits.
\n" ); document.write( "With the binomial, this is 200C50 *0.4^90*0.6^110, and that is only for 90 hits. One has to calculate 91, 92,
\n" ); document.write( "Normal approximation np=80 (mean)
\n" ); document.write( "np(1-p)=80*0.6=48 (variance)
\n" ); document.write( "sqrt 48 is 6.93
\n" ); document.write( "want z>(89.5-80)/6.83, and that is a lot easier to do.
\n" ); document.write( "
\n" );