To find the mean of a set, add up all of the numbers and divide by how many numbers you have. For the first set:
[tex]\mu=\frac{10.7+2.4}2=\frac{13.1}2=6.55[/tex]
For the second set:
[tex]\mu=\frac{13.7+2.5}2=\frac{16.2}2=8.1[/tex]
To find the mean absolute deviation, (MAD) find the mean of the distances of each number from the mean.
For the first set:
[tex]MAD=\frac{|10.7-6.55|+|2.4-6.55|}2=\frac{4.15+4.15}2=\frac{8.3}2=4.15[/tex]
For the second set:
[tex]MAD=\frac{|13.7-8.1|+|2.5-8.1|}2=\frac{5.6+5.6}2=\frac{11.2}2=5.6[/tex]
Note that when you only have two data points the mean is directly between them, which is why the distances are the same.
The means-to-MAD ratio is simply that, divide one by the other and that's it.
For the first set:
[tex]6.55\div4.15=1.57831325[/tex]
For the second set:
[tex]8.1\div5.6=1.44642857[/tex]
