PLZ HELP FASTEST CORRECT ANSWER WILL GET BRAINLIEST!

standard deviation: 2.582 (rounded)

mean: 7

Mean Definition:

The mean is the average(the sum of all of the numbers added together than divided by the amount of numbers.)

Mean Equation: (4+6+8+10)÷4=7

Standard Deviation Definition:

The standard deviation is a measure the amount of variation between the numbers.

Standard Deviation Equation:

just sum

10 + 10 = 20

= 5

step-by-step explanation:

to find the 15th term substitute n = 15 into the nth term formula

= (- 3 × 15 ) + 50 = - 45 + 50 = 5