<h2>
Answer:</h2>
Variance
<h2>
Step-by-step explanation:</h2>
The standard deviation is related to the variance. The standard deviation measures the variation or dispersion of a set of data and is represented by the Greek letter sigma
, while the variance measures how far a set of numbers are spread out from their average value. The variance is obtained by squaring the standard deviation, so the variance can be found as 
Answer:
x=65
Step-by-step explanation:
the sum of the angles of any triangle is equal to 180°. So, we do 180-50= 130. Then we divide 30 by two because there are two remaining angles so 130/2=65. x=65
Answer:
x= -8
Step-by-step explanation:
2x+3x-12=8x+12
5x-12=8x+12
5x-8x=12+12
-3x=24
24/-3
x= -8
ANSWER
Find out the how much fluid should be drained and replaced with pure antifreeze so that the new mixture is 60% antifreeze .
To proof
let us assume that the fluid should be drained and replaced with pure antifreeze be x .
As given
A radiator contains 10 quarts of fluid, 30% of which is antifreeze.
Now write 30% in the decimal form

Now write 60% in the decimal form

After drained and replaced the fluid with pure antifreeze than the quantity becomes = ( 10 - x )
The quantity of antifreeze is

The fluid should be drained and replaced with pure antifreeze so that the new mixture is 60% antifreeze .
than the equation becomes

solyving
100x +300 - 30x = 600
70x = 300

x = 4.28 quarts (approx)
Hence 4.28 quarts (approx) fluid should be drained and replaced with pure antifreeze so that the new mixture is 60% antifreeze .
Therefore the option (c.) is correct .