Question

Question #39e58

Answer 1

`30`

Explanation:

This is more properly a Statistics question than a Calculus one.

It is a "Combination" with 3 items in 4 locations, where the order is NOT important (you just want four pieces) and duplication is allowed (you might end up with all four of one item). The relevant formula is:

`((r + n - 1)!)/(r!(n-r)!)`

where n is the number of things to choose from, and we choose r of them (No repetition, order doesn't matter). The "!" means "factorial", or the digits of the number multiplied by each other.
https://www.mathsisfun.com/combinatorics/combinations-permutations.html

IN this case, n = 3 and r = 4.

`((r + n - 1)!)/(r!(n-r)!)` ; `((4 + 3 - 1)!)/(4!(3-4)!)`

`(1 xx 2 xx 3 xx 4 xx 5 xx 6)/(1 xx 2 xx 3 xx 4 xx (-1)!)`

`720/24 = 30`