Nationwide, the average waiting time until a electric utility customer service representative answers a call is 360 seconds. The Gigantic Kilowatt Energy Company randomly sampled 50 calls and found that, on average, they were answered in 335 seconds with a population standard deviation of 55 seconds. Can the company claim that they are faster than the average utility at α = 0.05?

solution:

as, mean is defined as sum of all the observations divided by total number of observations.

and , median is mid value of the data whether arranged in ascending order or descending order.

consider, roadsters:

2,3,4,5,6,7,8,9

mean =

also, median= , because number of observations is even, so median is mean of two mid values.

now, coming to bandits

2,3,4,5,6

mean =  

median = 4, as number of observations is odd.

so, roadsters has greater median as well mean than bandits.

→option a is true about the repairs performed on 2 types of cars:

bandits have lower median and mean than roadsters.

h/o/e/s mad

step-by-step explanation:

si si si

you didn't post any answer choices, so its not 100% clear what your teacher is looking for

however, log(15/7) is equivalent to log(15) - log(7)

i'm using the rule log(x/y) = log(x) - log(y)