Math Solutions [IBL]

Question, Holly, Sarah, Jen and Marsha are at a Zac Brown concert. A stage hand comes up to the group and tells them that three of them can go to the backstage to meet the band. How many different groupings are possible? If you have other solution kindly comment down on the comment section :)

Question, A license plate begins with three letters. If the possible letters are A, B, C, D and E, how many different permutations of these letters can be made if no letter is used more than once? If you have other solution kindly comment down.

In a particular high school, there are 6 Mathematics teachers, 5 Science teachers, 4 English teachers, and 4 Social Studies teachers. If a a teacher is randomly selected, what is the probability that the teacher is teaching Mathematics or Social Studies? Kindly comment down if you have other solutions. Thank You!

 Solving word problem using the formula of probability. If you have other solution on how to get this answer please comment down below.

Solving word problem using the formula of combination. If you have other solutions, kindly share it on the comment section below.  

Evaluating permutation and solving word problem. If you have other solutions, kindly share it on the comment section below.