Question
A series contains thirteen consecutive odd numbers. If the
average of these numbers is 41, determine the ratio of the first number to the last number in the sequence.Solution
ATQ,
Let the first number of the series be ‘x’.
2nd number will be = ‘x + 2’
So, the series becomes:
x, x + 2, x + 4, x + 6, x + 8, x + 10, x + 12, x + 14, x + 16, x + 18, x + 20, x + 22, x + 24
Average of series = (x + x + 24)/2 = x + 12
ATQ;
41 = x + 12
Or, x = 29
So, the last (13th) number = x + 24 = 29 + 24 = 53
Required ratio = 29:53
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