Answer: A. divided the difference of the two quantities by the sum of the two quantities.
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Explanation:
The difference of the quantities is 20-15 = 5
The sum of the quantities is 20+15 = 35
Dividing those results leads to 5/35 = 0.142857 which rounds to 0.1429
That converts to 14.29%
This is likely the path Adam took. This path is incorrect. The correct steps are shown below
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Difference = 20-15 = 5
Divide the difference over the original quantity
5/20 = 1/4 = 0.25 = 25%
We have a 25% decrease because the new quantity (15) is smaller than the old quantity (20)
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Here's another way to approach the problem
A = old value = 20
B = new value = 15
C = percent change
C = [ (B-A)/A ] * 100%
C = [ (15-20)/20 ] * 100%
C = (-5/20)*100%
C = -0.25*100%
C = -25%
The negative C value means we have a negative percent change, ie we have a percent decrease. So this is another way to get a 25% decrease.
Answer:
(i) Lowest Temperature: Warsaw
Highest Temperature: Cairo
(ii) 27.1 + 35.2 = 62.3°C
Answer:
y = -0.25x - 6
Step-by-step explanation:
You can either just read off the slope m = -0.25 and the intersection with the vertical n = -6 or you form a system of equations from points you choose on the graph. For example:
(0,-6);(4,-7)
The general equation for a line:
y = m*x + n
The two points on the graph form a system of two equations:
1. -6 = m*0 + n
2. -7 = m*4 + n
You can read off n right away fro equation 1:
n = -6
Plugging n into equation 2:
-7 = m*4 - 6 => -1 = m*4 => m = -1/4
Answer:
30%
Step-by-step explanation:
You add the total number of balls, which is 10. and then it is asking for brown balls and looking at the equation you know there are 3. so 3/10 is .30 which is 30%