Question

The marks in some post degree examination are Normally distributed mean= 500 and deviation = 100 we have to pass 550 students out of 674 students who are appearing in the examination. what should be the minimum marks for passing the examination​

Answer 1

Answer:

Given,

μ=500 (mean) 

σ=100 (standard deviation)

Tom does better than what percentage?

Tom got 585 marks

we will have to find how many students got less than 585

x<585 (find the probability)

converting the problem in standard form

Z=(x−μ)/σ

for x=585

Z=(585−500)/100=0.85

P(Z<0.85)=P(Z<0)+P(0<Z<0.85)

P(Z<0)=0.5

P(0<Z<0.85)=0.3023  (from Z- table)

so the total probability=0.5+0.3023=0.8023

so Tom got more than 80.23% of students

THANK YOU