The average of 15 numbers is 56 . The average of the first 8 numbers is 54.4 and that of the last 8 numbers is

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The average of 15 numbers is 56 . The average of the first 8 numbers is 54.4 and that of the last 8 numbers is 56.6 . If the 8^th number is excluded, then what is the average of the remaining numbers? (correct to one decimal place)

Accepted Answer

* Total sum of all 15 numbers = 15 × 56 = 840 Sum of first 8 numbers = 8 × 54.4 = 435.2 Sum of last 8 numbers = 8 × 56.6 = 452.8 Since the 8^th number is included in both the first 8 and the last 8 numbers: Sum of first 8 + Sum of last 8 = Sum of all 15 numbers + 8^th number 435.2 + 452.8 = 840 + 8^th number 888 = 840 + 8^th number 8^th number = 888 - 840 = 48 If the 8^th number is excluded: Sum of remaining 14 numbers = 840 - 48 = 792 The average of the remaining 14 numbers is: New Average = 79

The average of $15$ numbers is $56$ . The average of the first $8$ numbers is $54.4$ and that of the last $8$ numbers is $56.6$ . If the $8^{th}$ number is excluded, then what is the average of the remaining numbers? (correct to one decimal place)

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The average of 15 numbers is 56. The average of the first 8 numbers is 54.4 and that of the last 8 numbers is 56.6. If the 8th number is excluded, then what is the average of the remaining numbers? (correct to one decimal place)