Question
One-seventh of a 2-digit number is 15 less than half of
the number. What is the sum of the digits of the 2-digit number?Solution
Let the unit and tens digits of the numbers be p and q respectively. Hence, the number = 10q + p According to the question, 1/7 x (10q+p) = 1/2x (10q+p) - 15 5 /14× (10q+p) = 15 (10q+p) = 42 (10q+p) = 4 x 10 + 2 Hence, p = 4 and q = 2 Thus, (p+q) = 4 + 2 = 6 The sum of the 2-digit number is 6.
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