What is the simple way to solve questions like this - 10! divided by 8!
The long version to solving this would be 10x9x8x7x6x5x4x3 divided by 8x7x6x5x4x3x2x1, giving an amswer of 45.
Similarly, 6! divided by 3! would be 6x5x4 divided by 3x2x1 to give 20.
What is the simple way of solving problems like this, please?