Answer:
Hence the value of the test statistic is 0.780.
Step-by-step explanation:
Given:
Test Statistic:-
![t=\frac{\bar{X}-\mu }{\frac{S}{\sqrt{n}}}](https://tex.z-dn.net/?f=t%3D%5Cfrac%7B%5Cbar%7BX%7D-%5Cmu%20%7D%7B%5Cfrac%7BS%7D%7B%5Csqrt%7Bn%7D%7D%7D)
![t=\frac{11.2-10.8 }{\frac{1.7}{\sqrt{11}}}](https://tex.z-dn.net/?f=t%3D%5Cfrac%7B11.2-10.8%20%7D%7B%5Cfrac%7B1.7%7D%7B%5Csqrt%7B11%7D%7D%7D)
![t=\frac{0.4}{0.5126}\\t=0.780](https://tex.z-dn.net/?f=t%3D%5Cfrac%7B0.4%7D%7B0.5126%7D%5C%5Ct%3D0.780)
3.10+1.40= 4.50 nearest tenth
Answer:
11 years old
Step-by-step explanation:
If four brothers have the average age 6, then the sum of their ages is
![4\cdot 6=24](https://tex.z-dn.net/?f=4%5Ccdot%206%3D24)
years.
Let x years be the age of sister. If four brothers and their sister have the average age 7, then
![\dfrac{24+x}{5}=7.](https://tex.z-dn.net/?f=%5Cdfrac%7B24%2Bx%7D%7B5%7D%3D7.)
Multiply this equation by 5:
![24+x=35\Rightarrow x=35-24=11.](https://tex.z-dn.net/?f=24%2Bx%3D35%5CRightarrow%20x%3D35-24%3D11.)
The sister is 11 years old.
Answer:
102
Step-by-step explanation:
492.3069 rounded to the nearest thousandth is 492.307 :-)