5n is the mean of three numbers 391, n and n-1, find n

n = 30

Step-by-step explanation:

5n = Mean of three numbers

391 = 1st number

n = 2nd number

n - 1 = 3rd number

Therefore, to solve for x, we can write this equation:

(391 + n + n - 1)/3 = 5n

391 + 2n - 1 = 15n (Lowest Common Denominator is 3)

2n - 15n = -390 (Like terms)

-13n = -390

n = -390/-13

n = 30

Proof of n= 30 is correct:

(391 + n + n - 1)/3 = 5n

(391 + 30 + 29)/3 = 5 * 30

450/3 = 150

150 = 150

We proved n = 30 is correct

not enough information

step-by-step explanation:

we cannot know this, because the other students could have handed out 10 flyers, or they could have handed out 100. one way, the mean would go up, and another way, the mean would go down.

the correct answer is the second option