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What is the means-to-MAD ratio of the two data sets, expressed as a decimal?

Data set Mean Mean absolute deviation (MAD)
1 4.3 1
2 4.9 1.2

User Abdulaziz
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1 Answer

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Means-to-MAD ratio is something that wouldn't be hard to find out, but I've certainly never even heard of it.

The mean (µ) of a set of data points is found by adding them up and dividing by the number of data points.

For our first set:
\{1,\ 4.3,\ 1\}\rightarrow\frac{1+4.3+1}3=\frac{6.3}3=\boxed{2.1=\mu}

For our second set:
\{2,\ 4.9,\ 1.2\}\rightarrow\frac{2+4.9+1.2}3=\frac{8.1}3=\boxed{2.7=\mu}

The mean absolute deviation is when you find the distance of each data point from the mean and then find the mean of those distances.

For our first set:
\{1,\ 4.3\ 1\}\ has\ \mu=2.1.\\distances = \{1.1,\ 3.2,\ 1.1\}\rightarrow\frac{1.1+3.2+1.1}3=\frac{5.4}3=\boxed{1.8=MAD}

For our second set:
\{2,\ 4.9,\ 1.2\}\ has\ \mu=2.7\\distances=\{0.7,\ 2.2,\ 2.5\}\rightarrow\frac{0.7+2.2+2.5}3=\frac{5.4}3=\boxed{1.8=MAD}

It wouldn't be hard to find the ratio between these for each set as the question asks...don't forget to put our ratio in simplest form!

For the first set:
(\mu)/(MAD)=(2.1)/(1.8)=(21)/(18)=\boxed{\frac{7}6}

For the second set:
(\mu)/(MAD)=(2.7)/(1.8)=(27)/(18)=\frac{9}3=\boxed{\frac{3}1}
(In a fraction, we would just put this as 3 because the ÷1 is redundant...however, because this is ratio, we have to keep it in)


User Adam Byrtek
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