How many ways can a president, vis-president and treasurer be selected from a group of 15 students?

455ways

Step-by-step explanation:

This is expressed as 15 C 3 ( C- combination)

The concept of combination is used when we talk about selection.

Now we are selecting 3 from a sample of 15

15 C 3 = 15! / (15-3)! 3! = 15 ×14×13×12!/12!×3×2

= 5 × 7 × 13 = 455ways

answer: 2x + 2 − 2 = 10 − 2; subtraction property of equality

step-by-step explanation:

yes

step-by-step explanation:

yes