Answer:
[34,54]
Step-by-step explanation:
-The empirical rule states that the 95% of the sampled observations will fall within two standard deviations of the mean for a normally distributed population.
Where:
- 68% is the first standard deviation
- 95% is the second standard deviation about the mean
- 99.7% is the 3rd standard deviation about the mean.
-Therefore. the middle 95% interval is calculated as:
![CI=\mu+2\sigma\\\\=44\pm 2(5)\\\\=44\pm 10\\\\=[34,54]](https://tex.z-dn.net/?f=CI%3D%5Cmu%2B2%5Csigma%5C%5C%5C%5C%3D44%5Cpm%202%285%29%5C%5C%5C%5C%3D44%5Cpm%2010%5C%5C%5C%5C%3D%5B34%2C54%5D)
Hence, the interval is [34,54]
Answer:
23x = -115
Step-by-step explanation:
In the substitution method, you must solve for 1 variable in 1 equation to replace it in the other equation. For the system:
2x - 7y = 4
3x + y = -17
Solving for y in the second equation:
y = -17 - 3x
Replacing y in the first equation:
2x - 7(-17 - 3x) = 4
2x + 119 + 21x = 4
23x = -115
This is the new equation after use the substitution method.
She worked 4+3+6 hours = 13 hoursso 13x+10 = 120.50
13x=110.50
x=8.5
so she makes $8.50 an hour which is A.
I believe the answer is c