Question

The mean annual cost of car insurance is Rs 9450 and variance of Rs 2500. What is the probability that the average insurance cost of a sample of 25 cars will be between Rs 9400 and Rs 9500?

Answer 1

Answer:

The mean annual cost of car insurance is Rs 9450 and variance of Rs 2500. What is the probability that the average insurance cost of a sample of 25 cars will be between Rs 9400 and Rs 9500?

Answer 2

Answer:

Hence, the probability of that average insurance cost of a sample 25 cars is 0.6827.

Step-by-step explanation:

Given:

Mean annual cost of car insurance=9450

variance=2500

To find:

The probability that average insurance cost of a sample 25 cars.

Solution:

The mean annual cost of car insurance=9450

variance=2500

As we know, the formula of the probability, $X~N$( μ,δ^2/n)

Range can be written as, $p(-1 < z < 1)$

according to the given question, μ=9450,n=25, δ=2500

Hence, the probability that the average insurance cost of a sample of 25 cars can be written as, p(-1 < z < 1)

=$p((9400-9450)/2500/\sqrt{25}) < z < ((9500-9450)/2500/\sqrt{25)$

=0.6827

Hence, the probability of that average insurance cost of a sample 25 cars is 0.6827.