How do I calculate how many combinations of 4 letters each - using the following letters: A, B, C, D, E?

Answer 1

If the letters can repeat, it's 5*5*5*5=625

If the letters cannot repeat, then 5*4*3*2=120

Answer 2

20
5 letters by the comibnation of 4

Answer 3

If the letters can repeat: 5*5*5*5=625
If the letters can't repeat:5*4*3*2=120

Answer 4

You don't say if letters can be used more than once.
If so, the answer is 5 x 5 x 5 x 5 = 625
If all letters must be different, then 5 x4 x 3 x 2 = 120
Hope this helps.

Answer 5

Please be more specific. This can be thought of three ways.

1) If letters can be used only once and you don't care about the order of the letters:

(5C4) = 5!/{(4!)(1!)} = 5

Intuitively, you can make five combinations. Each combination has a different letter left out.
____________

2) If letters can be used only once and you do care about the order of the letters:

5*4*3*2 = 120

3) If letters can be repeated and you care about order:

5^4 = 625

Answer 6

5*5*5*5=625

^^^that's if you can repeat letters^^^

5*4*3*2=120

^^^ that's if you can't repeat letters

Answer 7

There are quite 3 ''sciences.'' the version between them is the degree of abstraction in touch. If we learn in basic terms the actual international with the aid of experimental remark, that's organic technology. we are able to additionally circulate in the direction of an better degree of abstraction by applying concerning numbers, that are outstanding from cloth issues. that's arithmetic. the optimal abstraction is as quickly as we handle being or fact itself, that's finished with the aid of metaphysics. All 3 of sciences are somewhat able to fixing their own problems with the use of their own approaches, and each and each technology has it quite is own technique. to observe the comparable technique to all 3 sciences creates a fallacy, the fallacy of the uniform technique of technology. as an occasion, we won't be able to say that, considering that relativity is actual in physics, mathematical equations are relative. i assume what i'm asserting is that, at the same time as i've got faith very strongly in God, the question of His life (or the life of *something,* quite) is a metaphysical question (bear in mind that ''metaphysical'' has a meaning very such as ''supernatural,'' if no longer a very virtually same meaning), quite than a mathematical question, and could be dealt with as such. Physics must be dealt with as physics, arithmetic must be dealt with as arithmetic, and metaphysics *enormously* must be dealt with as metaphysics.

Answer 8

^
|
what he said.