Question
The average of six numbers is 66. When two more numbers
are included, the average increases by 2. Find the average of the numbers included.Solution
Sum of the 6 numbers = 66 × 6 = 396
New average = 66 + 2 = 68
Sum of 8 numbers = 68 × 8 = 544
Sum of new 2 numbers = 544 - 396 = 148
Required average = 148 ÷ 2 = 74
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