Q9 of 13 Page 67

Find the sum of all two-digit numbers which are either multiple of 2 or 3.

Numbers divisible by both 2 and 3 are multiples of LCM of 2 and 3. So LCM of 2 and 3 is 6. Now the series is 6, 12, 18, 24…98

Sum of this series can be found by using arithmetic progression with first term 6 and common difference 6


Formula



N = 16



= 816


Hence answer is 816


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