Answer:
Step-by-step explanation:
We are given the letters:
2
We write the possible permutations of 3 letters from the given list:
3
Because order is not important in a combination we cross out the duplicate pairs:
4
Answer:
The students can group themselves in 360360 ways
Step-by-step explanation:
For this exercise we need to use the following equation:

This equation give us the number of assignation of n elements in k cell, where n1, n2, ..nk are the element that are in every cell
In this case we have 15 student that need to be assign in three vehicles with an specific capacity. This vehicles would be the equivalent to cells, so we can write the equation as:

Because the first vehicle have 7 seating, the second vehicle have 5 seating and the third vehicle have 3 seating.
Solving the equation we get 360360 ways to organized 15 students in three vehicles with capacity of 7, 5 and 3 seating.
That would first be a conversion factor is a number used to change one set of units to another, by multiplying or dividing. when a conversion is necessasry
For any sort of pyramid or cone, the volume is 1/3 of the volume of a prism with the same base and height. Since the volume of a prism/cylinder is

, the volume of a pyramid/cone is

.
In this case, our base is a circle, which has a radius of 4 cm.
The area of a circle is

where r is the radius.

We now know that our base is 16π cm.
We also know that our height is 9 cm.
Let's plug these into our volume formula.

Use 3.14 to approximate pi as the question states. 16 × 3.14 = 50.24.

We could punch all of that into our calculator to get the same answer, but since 1/3 of 9 is clearly 3, let's just go with that.
