Answer:
100
Step-by-step explanation:
it is a bit unclear to me, what that problem description means.
if I understand it correctly, than z is directly depending on x².
so, z = 16 for x = 2. x² = 4
I pondered a little bit, as there are several possibilities to connect 16 with 4 as a driving factor (e.g. 2⁴ = 16, 4×4 = 16, 12 + 4 = 16).
I decided to go with the simplest interpretation with the usual meaning of "varies" (multiplication) : 4×x²
that would mean
z = 4×x² = 4×5² = 4×25 = 100
20) Answer is: x=76
21) Answer is x=15
The difference in gallons per day used is 3.6.
The formula to calculate a z-score is:

,
where X is the value used to calculate the score, μ is the mean and σ is the standard deviation. We have the z-scores so we must work backward:

For both equations, we will cancel the 1.2 by multiplying both sides:

Now we will cancel 2.2 from both equations by adding it to both sides:
3.6+2.2=X-2.2+2.2 and 0+2.2=X-2.2+2.2
5.8=X and 2.2=X
The difference in gas used per day would be given by
5.8-2.2 = 3.6.
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<em>Hi there!</em>
<em>~</em>
<em>1:10000 would be the scale.</em>
<em>❀Hope this helped you!❀</em>
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