_________X=30____
_________-________
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
Answer:
All you need to do is to calculate the perimeter of the circle since you already had the diameter
Base on the picture, the perimeter should be:
C = d * π = 64 * 3.14 = 200.96 (m)
Answer:
Step-by-step explanation:
This is a system of equations. The 2 equations are:
4c + 2p = 16
2c + 3p = 12
Let's get rid of the p's first. Do this by multiplying the first equation by -3 and the second equation by 2 to get a new system that looks like this:
-12x - 6p = -48
4c + 6p = 24
Now add to get
-8c = -24 and
c = 3
That means that chocolate is $3 per pound. Now sub that back in to either one of the original equations to get the price for peanuts:
4(3) + 2p = 16 and
12 + 2p = 16 and
2p = 4 so
p = 2
The price for peanuts is $2 per pound.
1/3x=x-22
Add 22 to both sides to get 22+1/3x=x
Subtract 1/3x from both sides to get 22=2/3x
Multiply each side by 3/2 to get x=33!
