Question

The mean and standard deviation of marks of 500 students in an examination are 52 and 8 respectively. If the marks are normally distributed. Find Number of students getting marks between 48 and

Answer 1

Answer:

Step-by-step explanation:

ok so here, n=500

X1=45 and X2=60

mean m=55

std deviation s=12

for normal distribution, we need to convert X1 and X2 to Z1 and Z2

Z1=(X1-m)/s Z2=(X2-m)/s

on substituting values we get Z1=-0.83 and Z2=1.25

Now we see values of areas A1(-0.83) and A2(1.25), corresponding to Z1 and Z2 from cumulative normal distribution table.

A1=1-0.7967=0.2023 (Since Z1 is Negative)

A2=0.8944

Answer 2

Answer:

hdhdjdjdjdjjdudududuri

Step-by-step explanation:

jdjdidududp