5.3 minutes.
First, let's calculate the volume of the tank. That will be the area of the base multiplied by it's length. And since it's base is a circle, the area is pi*r^2. So:
V = l*pi*r^2
V = 3.5 * pi * (2.2/2)^2
V = 3.5 * pi * (1.1)^2
V = 3.5 * pi * 1.21
V = 4.235 * pi
V = 13.30464489
So the tank has a volume of about 13.3 ft^3. Now simply divide that volume
by the rate of incoming fluid. So
13.3 / 2.5 = 5.32
Rounding to 2 significant figures gives a time of 5.3 minutes.
The mean of 10 randomly selected students is definitely more likely to be closer to 75. 10 randomly selected students to include information and are more like to reflect the class’s scores. Consider an extreme example. Seventy-five students in a class of 100 earned perfect scores. The other 25 earned zeros. The average score of the class would be 75. A sample of 10 random students would almost certainly include more 100s then 0s, but both would be included in the sample. The mean of this samples score is closer to 75 than any individuals.
Answer:
Step-by-step explanation:
4 1/2
Do 2x4 = 8
Plus the 1 which is now 9/2
simplify and you get 4.5
