Answer:
![20,475\ ways](https://img.qammunity.org/2021/formulas/mathematics/middle-school/cgpzd95yst6qq1w8d9o57j3y1i45ygdz6u.png)
Explanation:
we know that
Combinations are a way to calculate the total outcomes of an event where order of the outcomes does not matter.
To calculate combinations, we will use the formula
![C(n,r)=(n!)/(r!(n-r)!)](https://img.qammunity.org/2021/formulas/mathematics/high-school/vqmwsxyof4bx13x4gbf5lrfpahqcms30yx.png)
where
n represents the total number of items
r represents the number of items being chosen at a time.
In this problem
![n=28\\r=4](https://img.qammunity.org/2021/formulas/mathematics/middle-school/51t1bvg9jfka3gqk9z4owl8kvry3i5ai28.png)
substitute
![C(28,4)=(28!)/(4!(28-4)!)\\\\C(28,4)=(28!)/(4!(24)!)](https://img.qammunity.org/2021/formulas/mathematics/middle-school/n413j40knss8l5y93ivxpl79cthtfewolj.png)
simplify
![C(28,4)=((28)(27)(26)(25)(24!))/(4!(24)!)\\\\C(28,4)=((28)(27)(26)(25))/((4)(3)(2)(1))\\\\C(28,4)=20,475\ ways](https://img.qammunity.org/2021/formulas/mathematics/middle-school/q73caaxde0s2oyuabpogllvex9vw1uvuio.png)