On discovering that her family had a 70% risk of heart attack, erin took a treadmill test to check her own potential of having a heart attack. the doctors told her that the reliability of the stress test is 67%. the test predicted that erin will not have a heart attack. what is the probability after the test was taken that she will have a heart attack?

0.4051
0.5010
0.4653
0.6632

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.