Normal Probability Distribution

IMPORTANT

Normal Probability Distribution: Overview

This topic covers concepts, such as, Probability Function, Continuous Random Variable, The Normal Approximation to Binomial Distribution & Continuity Correction etc.

Important Questions on Normal Probability Distribution

MEDIUM
IMPORTANT

X has Normal distribution with mean 2 and standard deviation 3. Find the value of the variable x such that the probability of the interval from the mean to that value is 0.4115.

HARD
IMPORTANT

In a normal distribution, 31% of the items are under 45 and 8% are over 64. Determine the mean and variance of the distribution.

HARD
IMPORTANT

In a normal distribution, 7% of the items are under 35 and 89% are under 63. Determine the variance of the distribution.

EASY
IMPORTANT

Sketch the event P29TL<32if the length of a local bus journey from ranjith's home to school is a normally distributed random variable TL with mean 31 minutes and standard deviation 5 minutes.

EASY
IMPORTANT

Sketch the event PTL31 if the length of a local bus journey from Raj' s home to school is a normally distributed random variable TL with mean 31 minutes and standard deviation 5 minutes.

HARD
IMPORTANT

A factory produces half-litre tins of oil. The volume of oil in a tin is normally distributed with mean 506.18ml and standard deviation 2.96ml. What percentage of the tins contain less than half a litre of oil? Use ϕ2.088=0.9816.

HARD
IMPORTANT

The mass of a newborn baby in a certain region is normally distributed with mean 3.35 kg and variance 0.0858 kg2. Estimate how many of the1356 babies born last year had masses of less than 3.5 kg. Use ϕ0.512=0.6957

HARD
IMPORTANT

For Z~N(0,1), find the probability P (Z-0.077)

HARD
IMPORTANT

For Z~N(0,1), find the probability of P (Z>-1.53)

HARD
IMPORTANT

For Z~N(0,1), find the probability of P (Z2.468). Use ϕ2.460.993

HARD
IMPORTANT

For Z~N(0,1), find the probability of P (Z<0.567)

HARD
IMPORTANT

The values in two datasets, whose probability distributions are both normal curves, are summarised by the following totals: On the same diagram, sketch a normal curve for each dataset.
Σx2=35000, Σx=12000 and n=5000.
Σy2=72000, Σy=26000 and n=10000.

EASY
IMPORTANT

X~Po42. Use the normal approximation to find: PX<50

EASY
IMPORTANT

State the null and alternative hypotheses and test statistic for a test for the population mean for the random variable X~N42, 8, sample value 45; two-tailed test at 10% level of significance.

EASY
IMPORTANT

Giving your answers to 3 significant figures, evaluate:

e-9

EASY
IMPORTANT

Giving your answers to 3 significant figures, evaluate:

e-3.6

EASY
IMPORTANT

Giving your answers to 3 significant figures, evaluate:

e-2

EASY
IMPORTANT

If X~N16, 1.8, find: P13<X<15 upto four decimal places.

EASY
IMPORTANT

If X~N16, 1.8, find: PX<20

(Correct the answer up to four decimal place)

EASY
IMPORTANT

Given that X~B120, 0.55, state a suitable approximating distribution and use it to find:

PX63