Step by step
The question
Question: compare the MAD of shop A, 10, 12, 14, and shop B, 8, 12, 16.
The MAD says how spread out the numbers are.
A smaller MAD means the numbers are closer together.
1 MAD of shop A
Shop A: the mean is the sum divided by how many.
The sum is 36.
There are 3 numbers.
36 divided by 3 is 12.
The distances from 12: 2, 0, 2.
They add up to 4.
Divided by 3: 1.3.
2 MAD of shop B
Shop B: the mean is the sum divided by how many.
The sum is 36.
There are 3 numbers.
36 divided by 3 is 12.
The distances from 12: 4, 0, 4.
They add up to 8.
Divided by 3: 2.7.
Careful!
The question is about spread.
So we compare the MADs, not the means.
3 Compare
1.3 is smaller.
So shop A is closer together: more consistent.
4 Check
Let's check with the lists: shop A goes from 10 to 14.
shop B goes from 8 to 16.
shop A is more bunched up.
So the answer is right!
Let's look back.
First: mAD of shop A.
Then: mAD of shop B.
Then: compare.
Last: check.