The standard deviation is the square root of the variance
so if the variance is 196, then the standard deviation is the sqrt of 196, which is 14
Answer:
Step-by-step explanation:
5y - 2y = 10
3y = 10
y = 10/3 = 3⅓
answer: x = 1/2
<u>explanation</u>
subtract 3x from both sides
4x+8=10
subtract 8 from both sides
4x=2
divide both sides by 4
x=2/4
simplify
x=1/2 OR x=.5
hope i helped!
X = amount of the 18% solution
y = amount of the 40% solution
we know the 18% solution has only 18% of alcohol, the rest is maybe water or something, now, how many liters is 18%? well, 18% of anything is just (18/100) * anything, so, 18% of x is just (18/100) *x or 0.18x, and that's how many liters are there.
likewise, how many liters are there in the 40% solution? well, (40/100) * y, or 0.4y, that many.
we know the mixture has to yield 10 liters at 20% alcohol, how many liters of only alcohol is that? well, (20/100) * 10, or 2 liters.


how much of the 40% solution? well y = 10 - x