15^x - 23.76
15 is how much each wash is
X is how many dogs she washes in a week
-23.76 is how much she paid for the shampoo
If you writ a graph start at (0,23.76)
X is the dogs she washes
Y the money she earned
150 + 20x, where x is the number of cellphones sold
Answer:
-1
Step-by-step explanation:
f(x) =2/3x -5
Let x = 6
f(6) = 2/3 (6) - 5
Multiply first
f(6) = 12/3 -5
= 4-5
= -1
Answer:
The correct option is;
![4\pm 2.63}\sqrt{\frac{3.2^{2}}{100}+\frac{2.1^{2}}{100}}](https://tex.z-dn.net/?f=4%5Cpm%202.63%7D%5Csqrt%7B%5Cfrac%7B3.2%5E%7B2%7D%7D%7B100%7D%2B%5Cfrac%7B2.1%5E%7B2%7D%7D%7B100%7D%7D)
Step-by-step explanation:
Here we have the formula for the confidence interval of the difference of two means where the population standard deviation is unknown based on the sample mean and sample standard deviation is given as follows;
![\left (\bar{x}_{1}- \bar{x}_{2} \right )\pm t_{\alpha /2}\sqrt{\frac{s_{1}^{2}}{n_{1}}+\frac{s_{2}^{2}}{n_{2}}}](https://tex.z-dn.net/?f=%5Cleft%20%28%5Cbar%7Bx%7D_%7B1%7D-%20%5Cbar%7Bx%7D_%7B2%7D%20%20%5Cright%20%29%5Cpm%20t_%7B%5Calpha%20%2F2%7D%5Csqrt%7B%5Cfrac%7Bs_%7B1%7D%5E%7B2%7D%7D%7Bn_%7B1%7D%7D%2B%5Cfrac%7Bs_%7B2%7D%5E%7B2%7D%7D%7Bn_%7B2%7D%7D%7D)
Where:
= Mean of the first sample = 22 grams
= Mean of the second sample = 18 grams
s₁ = Sample standard deviation of the first sample = 3.2 grams
s₂ = Sample standard deviation of the second sample = 2.1 grams
n₁ = Sample size of the first sample = 100
n₂ = Sample size of the second sample = 100
= t value obtained from tables at 99% confidence level and 100 degrees of freedom = 2.626 = 2.63
Therefore, plugging in the values, we have;
![\left (22- 18 \right )\pm 2.63}\sqrt{\frac{3.2^{2}}{100}+\frac{2.1^{2}}{100}} = 4\pm 2.63}\sqrt{\frac{3.2^{2}}{100}+\frac{2.1^{2}}{100}}](https://tex.z-dn.net/?f=%5Cleft%20%2822-%2018%20%20%5Cright%20%29%5Cpm%202.63%7D%5Csqrt%7B%5Cfrac%7B3.2%5E%7B2%7D%7D%7B100%7D%2B%5Cfrac%7B2.1%5E%7B2%7D%7D%7B100%7D%7D%20%3D%204%5Cpm%202.63%7D%5Csqrt%7B%5Cfrac%7B3.2%5E%7B2%7D%7D%7B100%7D%2B%5Cfrac%7B2.1%5E%7B2%7D%7D%7B100%7D%7D)
Therefore, the correct option is
.
Answer:
Step-by-step explanation:
Given in the data set as
26, 34, 38, 49, 65, 76, 81
Sum = 369
No of entries = 7
Mean =52.71
When 1213 is included
New sum = 1582
No of entries =8
New mean = 197.75
Thus mean increases by 145.04