We know the diameter, so we can easily find the radius. The diameter is twice as long as the radius, so we divide the diameter by 2 to find the radius. This is equal to 6/2 = 3. Now, we plug our numbers into the formula.
This could also be written:
Both 27 pi cubic meters and 84.82 cubic meters are correct answers, so choose whichever one you think your teacher would prefer.
The formula of the volume of a cylinder is: V = PI (3.14) times radius squared times height, so... V = PI times half of the diameter, which is 3, squared and times by 3 (the meters of height). Now, V = PI times 9 times 3. PI (3.14) times 9 = 28.26 times 3 = 84.78. So, the volume of the cylindrical tank is 84.78 meters cubed (volume is always cubed).
If there are 12 boys and 13 girls, there are 25 kids in the class total. This means that 13/25 are girls. In order to know the probability, you must divide 13 by 25, which gets an answer of 0.52, which is equal to 52%.