Question

A dog trainer compared mean numbers of lessons for two

groups of dogs to learn a new trick.

Mean number of lessons Mean Absolute Deviation (MAD)

Group A 5

Group B 3

2

2

Which statement about the data is true?

The mean number of lessons for group A is greater than the mean

for group B by 1 MAD

B. The mean number of lessons for group A is greater than the mean

for group B by 2 MAD

C. The MAD for group A is more than the MAD for group B

D. On average, the dogs in group B required more lessons than the

dogs in group A

Answer 1

The mean number of lessons for group A is greater than the mean for group B by 1 MAD.

Explanation:

Test approved

Answer 2

The mean number of lessons for group A is greater than the mean for group B by 1 MAD

Explanation:

Given the table :

_______Mean number of lessons ____ MAD

GRP A _____ 5 ___________________ 2

GRP B _____ 3 ___________________ 2

With group A having a mean number of lessons of 5 and Group B having a mean number of lessons of 3

Mean of A > mean of B ; hence, Group A dlgs tool more lessons to learn the trick than group B dogs.

The mean absolute deviation (MAD), measures how far a value is from the mean

Difference in mean number of lessons :

5 - 3 = 2

2 lessons ;

Number of mean absolute deviations:

Difference / MAD value = 2 / 2 = 1