Question
Average 20 numbers is ‘x’. If the average of first
12 numbers is 75.5 while average of last 5 numbers is 86.6 and 13th, 14th and 15th numbers are (3x - 25), (2x + 50) and 175 respectively. Find the 14th number.Solution
According to question, => 20x = 75.5 × 12 + 86.6 × 5 + 3x – 25 + 2x + 50 + 175 => 15x = 1539 => x = 102.6 Therefore, 14th number = 2 × 102.6 + 50 = 255.2
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