1. ## I can not get the answer from the book could you please explain

Estimate the volume in metric units and compute the acual volume of the item:

Oil in a barrel that has a height of 1 m and a diameter of 0.5m

The answer in the book: 0.20mcubed

2. Originally Posted by camstill
Estimate the volume in metric units and compute the acual volume of the item:

Oil in a barrel that has a height of 1 m and a diameter of 0.5m

The answer in the book: 0.20mcubed
The barrel is a cylinder I assume ....? With radius r = 0.25 m ....

3. So don't you use the formula V=(pi)(rsquared)(l)

and I still don't get that answer

4. $\displaystyle V = \pi r^2h$

$\displaystyle r = \frac {d}{2} = \frac{0.5\ m}{2} = 0.25\ m.$

$\displaystyle \Rightarrow V = \pi \times (0.25)^2 \times 1$

$\displaystyle \Rightarrow V = 0.20\ m^3$ (correct to $\displaystyle 2$ sig. fig.)

I hope that helps.

ILoveMaths07.

5. Originally Posted by camstill
So don't you use the formula V=(pi)(rsquared)(l)

and I still don't get that answer
Then you're making a data entry error with your calculator.