How do you find the missing number when you have four numbers but missing the fifth. Find the average of 12.3 with the numbers of 12.8,12.6,11.8,9.7

Answer 1

5 * 12.3 = 61.5

That is the total of the 5 numbers with that average.

So, the missing number is 61.5 minus the sum of the first 4 numbers.

Answer 2

5 * 12.3 = 61.5

12.8 + 12.6 + 11.8 + 9.7 = 46.9

61.5 - 46.9 = 14.6