Question
Out of 6 numbers, the sum of the first 5 numbers is 7
times the number. If their average is 136, then the 6th number is:Solution
Average of 6 numbers = 136 (average = sum of terms/number of terms) Sum of 6 numbers = 136 × 6 = 816 ---(1) Let the 6th number be x. Sum of 5 numbers = 7x From eq(1), 7x + x = 816 x = 816/8 = 102 The 6th number is 102.
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