Answer:
c=8
Step-by-step explanation:
-3(2c+5)=33
-6c-15=33
-6c=33+15
-6c=48
c=48/6
c=8
When ever you have percentages, it should be helpful to bear in mind you can express them as multipliers. In this case, it will be helpful.
So, if we let:
a = test score
b = target score
then, using the information given:
a = 1.1b + 1
a = 1.15b - 3
and we get simultaneous equations.
'1.1' and '1.15' are the multipliers that I got using the percentages. Multiplying a value by 1.1 is the equivalent of increasing the value by 10%. If you multiplied it by 0.1 (which is the same as dividing by 10), you would get just 10% of the value.
Back to the simultaneous equations, we can just solve them now:
There are a number of ways to do this but I will use my preferred method:
Rearrange to express in terms of b:
a = 1.1b + 1
then b = (a - 1)/1.1
a = 1.15b - 3
then b = (a + 3)/1.15
Since they are both equal to b, they are of the same value so we can set them equal to each other and solve for a:
(a - 1)/1.1 = (a + 3)/1.15
1.15 * (a - 1) = 1.1 * (a + 3)
1.15a - 1.15 = 1.1a + 3.3
0.05a = 4.45
a = 89
2x-1=x^2
If you plug these two equations into a graphing calculator, like desmos.com, you can see that the two lines will intersect at (1, 1).
Answer:
1.5
Step-by-step explanation: 3 divided by 1/2 is 1.5.
Answer:
13/20 = 65%
Step-by-step explanation:
1/4 = 25%
7/10 = 70%
13/20 = 65%
Only the last one had the correct percentage.
