document.write( "Question 1150680: The annual rate of return on investment in “Apple Company Fund” is normally distributed with mean of 20% and a standard deviation of 40%.
\n" );
document.write( "(i) What is the probability that the annual rate of return on investment in “Apple Company Fund” is between 5% and 50%?
\n" );
document.write( "(ii) Determine the annual rate of return such that the probability of exceeding it is 0.05. \n" );
document.write( "
Algebra.Com's Answer #772245 by Theo(13342) You can put this solution on YOUR website! i get the following.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "mean is 20% and standard deviation is 40%.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "probability the rate of return is between 5% and 50% is equal to .4195.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "annual rate of return such that the probability of exceeding it is .05 would be 85.794%.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "here are the visuals.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \r\n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \r\n" ); document.write( " \n" ); document.write( "\n" ); document.write( "if you don't have such a calculator as the one i used (found at http://davidmlane.com/hyperstat/z_table.html), then you might have to work with z-scores as shown below.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "i)\r \n" ); document.write( "\n" ); document.write( "z-score for annual rate of return of .05 is z = (5 - 20 / 40 = -.375.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "z-score for annual rate of return of .5 is z = (50 - 20) / 40 = .75\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "area under the normal distribution curve to the left of z = -.375 = .35383.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "area under the normal distribution curve to the left of z = .75 = .77337\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "area in between = .77337 - .35383 = .4195 rounded to 4 decimal places.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "z-score that has area to the right of it of .05 is the same as z-score that has area of .95 to the left of it.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "z-score with area of .95 to the left of it is equal to 1.64485.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "raw score associated with that z-score is 1.64485 = (x - 20) / 40.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "solve for x to get x = 1.64485 * 40 + 20 = 85.794.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "i worked with percents, but you could also work with rates.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "rate = percent / 100 \n" ); document.write( "percent = rate * 100\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "the z-score formula is z = (x - m) / s\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "z is the z-score \n" ); document.write( "x is the raw score \n" ); document.write( "m is the raw mean \n" ); document.write( "s is the standard deviation or the standard error. \n" ); document.write( "in this case, standard deviation is used. \n" ); document.write( " \n" ); document.write( " |