The time required to finish a test in normally distributed with a mean of 40 minutes and a standard deviation of 8 minutes. What is the probability that a student chosen at random will finish the test in between 32 and 56 minutes?
16%
82%
34%
2%

so this is normal distribution and i don't understand it at allll

Question

The time required to finish a test in normally distributed with a mean of 40 minutes and a standard deviation of 8 minutes. What is the probability that a student chosen at random will finish the test in between 32 and 56 minutes?
	16%
	82%
	34%
	2%

so this is normal distribution and i don't understand it at allll

anonymous · Answer

for some reason i can't get normal distribution

anonymous · Answer

you need to find z corresponding to 32 and 56 respectively
z= (x- mean)/sd
for 32 
wehave z1 = (32 - 40)/8= -1
for 56 z2 = (56-40)/8  = 2

anonymous · Answer

now you need the area from the normal distribution table between z2 and z1

anonymous · Answer

oh oh ok!

anonymous · Answer

im understanding it. slowly. but its coming

anonymous · Answer

34?