The sum of 9 consecutive numbers is 279. what is the sum of the first and the last number

62

Step-by-step explanation:

The first number = y

2nd number = y + 1

3rd number = y + 2

4th number = y + 3

5th number = y + 4

6th number = y + 5

7th number = y + 6

8th number = y + 7

9th number = x + 8

y + y + 1 + y + 2 + y + 3 + y + 4 + y + 5 + y + 6 + y + 7 + y + 8 = 279

9y + 36 = 279

9y + 36 - 36 = 279 - 36

9y = 243

9y ÷ 9 = 243 ÷ 9

y = 27

y + 8 = 27 + 8

27 + 8 = 35

35 + 27 = 62

12.4, 12.387, 12.26, 12.252, 6.241, 6.2, 6.015, 6.009, 1.411, 1.2, 1.056, 1.007, 0.31,   0.13, 0.5, 0.04

step-by-step explanation:

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