2(x+4)=16
multiply the bracket by 2
(2)(x)=2x
(2)(4)=8
2x+8=16
move 8 to the other side, sign changes from +8 to -8
2x+8-8=16-8
2x=16-8
2x=8
divide both sides by 2 to get x by itself
2x/2=8/2
Answer:
x=4
Answer:
0.13% of customers spend more than 46 minutes
Step-by-step explanation:
Problems of normally distributed samples are solved using the z-score formula.
In a set with mean
and standard deviation
, the zscore of a measure X is given by:
![Z = \frac{X - \mu}{\sigma}](https://tex.z-dn.net/?f=Z%20%3D%20%5Cfrac%7BX%20-%20%5Cmu%7D%7B%5Csigma%7D)
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
In this problem, we have that:
![\mu = 40, \sigma = 2](https://tex.z-dn.net/?f=%5Cmu%20%3D%2040%2C%20%5Csigma%20%3D%202)
What percentage of customers spend more than 46 minutes?
This is 1 subtracted by the pvalue of Z when X = 46. So
![Z = \frac{X - \mu}{\sigma}](https://tex.z-dn.net/?f=Z%20%3D%20%5Cfrac%7BX%20-%20%5Cmu%7D%7B%5Csigma%7D)
![Z = \frac{46 - 40}{2}](https://tex.z-dn.net/?f=Z%20%3D%20%5Cfrac%7B46%20-%2040%7D%7B2%7D)
![Z = 3](https://tex.z-dn.net/?f=Z%20%3D%203)
has a pvalue of 0.9987
1 - 0.9987 = 0.0013
0.13% of customers spend more than 46 minutes
So 1 gallon of window cleaner
1 part is cleaner
3 part is water
so therefor
1/(1+3)=1/4=cleaner
3/4=water
1 gallon=4 quarts
1 quart cleaner
3 quart water
1 quart
Answer:
18 3/4 miles
Step-by-step explanation:
convert fractions into decimals and multiply 12.5 by 1.5 to get your answer and then convert back to fractions