Question

Find the area under the standard normal curve between z=−0.88 and z=−0.78. Round your answer to four decimal places, if necessary.

Answer 1

we have to find   --------- (1)

we know that

After substituting a=0.78 we have:

P ( Z<−0.78)=1−P ( Z<0.78 )

from normal table

P ( Z<0.78 )=0.7823

P ( Z<−0.78)=1−P ( Z<0.78 )=1−0.7823=0.2177 ---------------- 2

similiarly

P ( Z<−0.88)=1−P ( Z<0.88 )

P ( Z<−0.88)=1−P ( Z<0.88 )=1−0.8106=0.1894----------------3

using 2 and 3 in 1 we have

P (−0.88<Z<−0.78 )=0.2177-0.1894 = 0.0283