Answer:
x = -8/5
Step-by-step explanation:
-3(x+4) -> -3x-12
-3x-12=7x+4
-7x
-10x-12=4
+12
-10x=16
16/-10 = -8/5
-8/5 = x
Answer: 9.70%
Step-by-step explanation:
The formula to find the percentage error is given by :-
![\%\text{ error}=\dfrac{|\text{Estimate-Actual}|}{\text{Actual}}\times100](https://tex.z-dn.net/?f=%5C%25%5Ctext%7B%20error%7D%3D%5Cdfrac%7B%7C%5Ctext%7BEstimate-Actual%7D%7C%7D%7B%5Ctext%7BActual%7D%7D%5Ctimes100)
Given : Actual mass of zinc oxide used by pharmacist = 28.35 g
Estimated mass of zinc oxide used by pharmacist =31.1 g
Now, ![\%\text{ error}=\dfrac{|31.1-28.35|}{28.35}\times100](https://tex.z-dn.net/?f=%5C%25%5Ctext%7B%20error%7D%3D%5Cdfrac%7B%7C31.1-28.35%7C%7D%7B28.35%7D%5Ctimes100)
i.e. ![\%\text{ error}=\dfrac{2.75}{28.35}\times100](https://tex.z-dn.net/?f=%5C%25%5Ctext%7B%20error%7D%3D%5Cdfrac%7B2.75%7D%7B28.35%7D%5Ctimes100)
i.e. ![\%\text{ error}=9.70017636684\approx9.70\%](https://tex.z-dn.net/?f=%5C%25%5Ctext%7B%20error%7D%3D9.70017636684%5Capprox9.70%5C%25)
Hence, the percentage of error on the basis of the desired quantity.= 9.70%
There are 8 ounces in a cup, so there are 125 cups in 1000 ounces.
1000 / 8 = 125
there are 60 minutes in an hour and 120 minutes in 2 hours
so 1000 ounces / 2 hours is
125 cups / 120 minutes
125 / 120 = 1.04 cups per minute
Check your work
multiply times 60 to get cups per hour
1.04 * 60 = 62.4 cups per hour
multiply times 8 to get ounces per hour
62.4 * 8 = 499.2
multiply times 2 to get ounces per 2 hours
499.2 * 2 = 998.4
the number is not quite 1000 due to rounding the 125 / 120 as it is closer to 1.041666666666667
The answer would be $102.14 if you divide 255.35 by 5 then multiply it by 2, you'll get 102.14
255.35 divided by 5 = 51.07 x 2 = 102.14
Hope this helps! ;)