document.write( "Question 1150692: John can take on three possible routes from his home to his oce in the
\n" ); document.write( "morning. The percentage of days on routes A, B, and C to his oce were 45%,
\n" ); document.write( "30%, and 25%, respectively. The travelling time on each of these routes is
\n" ); document.write( "normally distributed with mean and standard deviation given in the following
\n" ); document.write( "table:\r
\n" ); document.write( "\n" ); document.write( "Mean:
\n" ); document.write( "Route A 30 minutes
\n" ); document.write( "Route B 35 minutes
\n" ); document.write( "Route C 28 minutes\r
\n" ); document.write( "\n" ); document.write( "Standard Deviation
\n" ); document.write( "A . 10 minutes
\n" ); document.write( "B . 8 minutes
\n" ); document.write( "C . 12 minutes\r
\n" ); document.write( "\n" ); document.write( "John left his home at 8:28am and arrived at his oce before 9:00am. Calculate
\n" ); document.write( "the probability that he took Route B to work? \n" ); document.write( "

Algebra.Com's Answer #772354 by Glaviolette(140) $\"\"$ $\"About$

You can put this solution on YOUR website!
The travel time was less than 32 minutes. Use that as X in the z-score formula. Therefore, z = (32-35)/8 = -0.375 = -0.38. From a z-table, area less than -0.38 is 0.3520. Therefore, the probability that he took route B, is .3520. \n" ); document.write( "

\n" );