If you were to flip the discs on the side so that the height is 1.6 cm, you cannot fit 16 of those in the 20 cm high box. The most you can fit is 12.
Basically it means how many ways can you choose 2 things out of 4 things in which the order of the 2 things matter.
\(P{4 \choose 2}=\frac{4!}{(4-2)!}=\frac{4*3*2*1}{2*1}\)
Why?
\(P{4 \choose 2}\)
I do not understand what you are confused on. 3! means 3 * 2 * 1. Also, you cannot apply factorial to other problems like this (I just used it to represent my answer).
Yeah whatever
I basically gave you the answer last time you posted it. Each quadrilateral has 4 right triangles. Count how many quadrilaterals there are and multiply that by 3. It should take less than 2 seconds.
I know. It's just that it will be lots of work.
Aw, but 0 can be very large in a world of negative numbers. I guess we live in a positive world then. Why am I having senseless thoughts.
There are ten rooms
