Question
The average of a set of 's' numbers is 45. If 180 is
added to the set, then the average of the set becomes 45.2. Find the value of '4 X (s - 18)'.Solution
Sum of all 's' numbers = 45s
ATQ:
(45s + 180) / (s + 1) = 45.2
Multiplying both sides by (s + 1):
45s + 180 = 45.2(s + 1)
45s + 180 = 45.2s + 45.2
180 - 45.2 = 45.2s - 45s
134.8 = 0.2s
s = 674
4 X (s - 18):
4 X (674 - 18) = 4 X 656 = 2624
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