He will mix some 20% solution and some 70% solution to make 60% solution.
Let x = number of liters of 20% solution.
Let y = number of liters of 70% solution.
He wants to make 50 liters of 60% solution, so
x + y = 50 First Equation
The amount of acid in x amount of 20% solution is 20% of x, or 0.2x
The amount of acid in y amount of 70% solution is 70% of y, or 0.7y
The amount of acid in 50 liters of 60% solution is 60% of 50 liters, or 0.6 * 50 = 30
Now we add the amounts of acid.
0.2x + 0.7y = 30 Second Equation
x + y = 50
0.2x + 0.7y = 30
-0.2x - 0.2y = -10
0.2x + 0.7y = 30
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0.5y = 20
y = 40
x + y = 50
x + 40 = 50
x = 10
Answer: He needs 10 liters of 20% solution and 40 liters of 70% solution.
Answer:
0.9544
Step-by-step explanation:
P(-2 < Z < 2) means that Z has mean 0 and standard deviation 2.
P(−2 < Z < 2) = F(2) - F(-2)
Using the Z - table,
F(2) = 0.9772
and F(-2) = 0.0228
Thus,
P(−2 < Z < 2) = 0.9772 - 0.0228 = 0.9544
This means that data within two standard deviation is 95%.
Answer:
y = 0.125x + -1.375
Step-by-step explanation:
You can try and use desmos.com to help you graph these 2 points. My algebra teacher recommended it if you don't have a physical graphing calculator!
Answer:33/9
Step-by-step explanation:
Log10(x+3)-Log10(x-3)=1
Log10((x+3)/(x-3))=1
(x+3)/(x-3)=10^1
(x+3)/(x-3)=10
Cross multiply
x+3=10(x-3)
Open brackets
x+3=10x-30
Collect like terms
10x-x=30+3
9x=33
Divide both sides by 9
9x/9=33/9
x=33/9
