Answer: Percent change = 20%
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Work Shown:
A = old value = 25 (last week's number)
B = new value = 30 (current week's number)
C = percent change
C = [ (B-A)/A ] * 100%
C = [ (30-25)/25 ] * 100%
C = [ 5/25 ] * 100%
C = 0.20* 100%
C = 20%
The percent change is 20%
The positive value of C indicates we have a percent increase.
Plug in the x+3 for y.
8x-x+3=12
7x=9
X=1.3
Then, y= -0.25
Answer is 2263.
Checkpoint 1 is -86
Checkpoint 4 is 2177
Subtract -86 from 2177....2177-(-86)
=2263
2263 is how much higher checkpoint 1 (-86) is from checkpoint 4 (2177)
Hope this helps! :)
Because the decimal is over 40 the answer is 15
The first thing we must do for this case is to define variables:
x: the total mass of the chemical in the container
y: a sample of a chemical from a container
We have the following equation:
y = (3/10) x - 5 3/4
Then, for y = 39.1 we have:
39.1 = (3/10) x - 5 3/4
Clearing x:
(3/10) x = 39.1 + 5 3/4
(3/10) x = 44.85
x = (10/3) * (44.85)
x = 149.5 grams
Answer:
the total mass in grams of the chemical in the container before the scientist removed the sample of 39.1 grams was:
x = 149.5 grams.
