Find P82 x 87Solutionso p82

Find P(82 x 87)

Solution

so, p(82<=x <=87) = P(x<=87) - p( x<82) = p( (x-mean)/s.d <= (87-86)/7 ) -  p( (x-mean)/s.d < (82-86)/7 )
= p ( z <= 0.1429) - p( z < -0.5714) = 0.5568154 - 0.2838643 =  0.2729512...

To find this p-values you can use a Normal distribution table or you can use any software! like excel!..
you have to type in a cell... =NORMSDIST( 0.1429)-NORMSDIST( -0.5714).....