Bob is doing a quality test on machine bolts. He tested 24 bolts that he randomly picked and found that 5 were defective Based on Bob's results, what is the expected number of bolts that will be defective if he tests 840 bolts?

Mean of the binomial distribution

μ = 174.972 bolts

Step-by-step explanation:

Step(i):-

Given that Bob tested 24 bolts that he randomly picked and found that 5 were defective

The proportion of the defective item

Step(ii):-

Let 'x' be a random variable in a binomial distribution

Mean of the binomial distribution

                   μ = np

                  μ = 840 ×0.280

                 μ = 174.972

Final answer:-

Mean of the binomial distribution  μ = 174.972 bolts

3

step-by-step explanation:

in standard form:

a= dictionaries

b= maps

you have to buy 3 dictionaries, so put a 3 next to the a (dictionaries) so that you can multiply them by each other.

a3+b= 60 (the amount of money you have)

we already know the cost of a=15 so replace a with $15

($15 x 3)+b=60

multiply 15 and 3 to get $45 and replace it with $45

45+b=60

and then replace b with 15 to get the total:

45+15=60

that means you have $15 left after buying 3 dictionaries.

15 divided by the cost of a map ($5) equals 3.

so you can buy 3 maps.

sorry if it was confusing!