The probability that an appliance is in repair is 0.8. if an apartment complex has 100 such appliances, what is the probability that at least 90 will be in repair? use the normal approximation to the binomial.

Step-by-step explanation:

This situation can be modeled by a binomial distribution of parameters:

We want to find the probability that at least 90 are in repair.

We can approximate this problem to a normal distribution, where:

Then we look for

Then we must find the normal standard statistic Z-score

Therefore:

Looking in the standard normal table we obtain:

to find the unit price of an object, you divide the price by object. you are trying to find out how much an object cost per unit.

for instance, lets say you have 50lb of ice cream(object) that cost 8.00 dollars(price). to find the unit cost, we take the 8.00 and divide it by 50, which will give us .16 cents per pound. we can check this by multiplying .16 by 50 = 8.00

so

object = e2

price = d2

unit price = c2

formula for c2:

=d2 / e2

so in my example about ice cream, we would have the following.

e2 = 50

d2 = 8.00

c2 formula:

=d2 / e2