Question
The average of five even numbers is 74. If we replace
two of these even numbers, 84 and 96, with a single even number X, the new average decreases by 4. What is the value of X?Solution
Sum of 5 even numbers = 5 x 74 = 370 Sum of after 2 replacing even numbers by X = 370 - (84 + 96) + X = 370 - 180 + X Now Sum of 4 even numbers = (74 - 4) x 4 = 280 According the question, we get 370 – 180 + X = 280 X = 280 – 370 + 180 X = 90
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