Question
Average 20 numbers is ‘x’. If the average of first
12 numbers is 72.5 while average of last 5 numbers is 86.8 and 13th, 14th and 15th numbers are (3x - 48), (x + 54) and 186 respectively. Find the 14th number.Solution
According to question, => 20x = 72.5 × 12 + 86.8 × 5 + 3x – 48 + x + 54 + 186 => 16x = 1496 => x = 93.5 Therefore, 14th number = 93.5 + 54 = 147.5
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