The average of 19 numbers is 22.8. The average of the first ten numbers is 18.4 and that of the last ten numbers is 28.6. If the number is excluded from the given numbers, then what is the average of the remaining numbers? (Your answer should be nearest to an integer.)
Answer & explanation
Correct answer: option 3
Sum of 19 numbers = 22.8 x 19 = 433.2
Sum of first 10 numbers = 18.4 x 10 = 184
Sum of last 10 numbers = 28.6 x 10 = 286
10th number = 286 + 184 - 433.2 = 36.8
Sum of 18 number = 433.2 - 36.8 = 396.4
Average of 18 number = \(\frac{396.4}{18}\) = 22