Answer: number 3 4 5
Step-by-step explanation:hope this helps!
Answer:
D
A=-5
Step-by-step explanation:
Answer:
z = -12
Step-by-step explanation:
The given system of equations is:
xy/(x + y) = 1 ...........................(1)
xz/(x + z) = 2...........................(2)
yz/(y + z) = 3...........................(3)
From (1): x + y = xy
=> y = xy - x
y = x(y - 1)
x = y/(y - 1).......................................(4)
From (2): 2(x + z) = xz
=> 2x + 2z = xz
2x = xz - 2z
2x = z(x - 2)
z = 2x/(x - 2) ....................................(5)
From (3): 3(y + z) = yz
=> 3y + 3z = yz
3y = yz - 3z
3y = z(y - 3)
z = 3y/(y - 3)....................................(6)
Comparing (5) and (6)
2x/(x - 2) = 3y/(y - 3)
2x(y - 3) = 3y(x - 2)
2xy - 6x = 3xy - 6y
6(y - x) = xy .................................(7)
But from (1): xy = x + y
Using this in (7), we have
6(y - x) = x + y
6y - y - 6x - x = 0
5y - 7x = 0
5y = 7x
x = 5y/7................................................(8)
Using this in (4)
5y/7 = y/(y - 1)
1/(y - 1) = 5/7
(y - 1) = 7/5
y = 1 + 7/5
y = 12/5..........................................(9)
Using this in (8)
x = 5(12/5)/7 = 12/7 .......................(10)
Using (10) in (5)
z = 2x/(x - 2)
z = 2(12/7) ÷ (12/7 - 2)
= 24/7 ÷ -2/7
= 24/7 × (-7/2)
= -24/2 = -12
z = -12.
As a formula, you're saying 4*(n-7)=32
This solves to n-7 = 8, so n=15
Answer:
There is evidence for the claim that less than 10% of the test results are wrong
Step-by-step explanation:
Given that the company Drug Test Success provides a "1-Panel-THC" test for marihuana usage.
Among 300 tested subjects, results from 27 subjects were wrong (either a false positive or a false negative.)
Sample proportion = 
H0: p = 0.10
Ha: p <0.10
(left tailed test)
p difference = 0.09-0.10 = -0.01
Std error = 
z statistic = -1.9245
p value = 0.027
Since p <0.05 we reject H0
There is evidence for the claim that less than 10% of the test results are wrong
