X=15% alloy
y=8% alloy
x+y=40
y=40-x
0.15x+0.08y=40*0.10
0.15x+0.08(40-x)=40*0.1
times 100 both sides for easy
15x+8(40-x)=400
15x+320-8x=400
7x+320=400
minus 320 from both sides
7x=80
divide both sides by 7
x=80/7
x+y=40
80/7+y=280/7
y=200/7
aprox
x=11.4lb
y=28.6lb
11.4lb of 15%
28.6lb of the 8%
what????
Answer:
The standard deviation is $26.67.
Step-by-step explanation:
Problems of normally distributed samples are solved using the z-score formula.
In a set with mean 
and standard deviation 
, the zscore of a measure X is given by:
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
In this problem, we have that:
Assuming a normal distribution, if 70 percent of the filings cost less than $171.00, what is the standard deviation?
This means that when X = 171, Z has a pvalue of 0.7. So when Z = 0.525.
The standard deviation is $26.67.
Step-by-step explanation:
10. 8a - 12b
11. d^8
12. 3y^3
13. 4a+b
14. 11x-3
15. 2a^2+2ab
16. 2x^3+x
17. 4(a+2)
18. 3m(m-3)
(ab+3)(ab−3)
=(ab+3)(ab+−3)
=(ab)(ab)+(ab)(−3)+(3)(ab)+(3)(−3)
=a^2b^2−3ab+3ab−9
=a^2b^2−9
Answer:
x = -2
Step-by-step explanation:
So we are given the equation -3(3x + 3) = -2x + 5 and we are solving for x. We will have to try to get the equation into the form x = _. That would be our answer.
-3(3x + 3) = -2x + 5
Distribute the -3 on the left side.
-9x - 9 = -2x + 5
Add 2x to both sides to get rid of the -2x on the right side.
-9x - 9 + 2x = 5
Simplify.
-7x - 9 = 5
Add 9 to both sides to get rid of the - 9 on the left side.
-7x = 5 + 9
Simplify.
-7x = 14
Divide both sides by -7 to get rid of the coefficient of -7 on the left side.
x = 14 ÷ (-7)
Simplify.
x = -2
The answer is x = -2.
I hope you find my answer helpful. :)
