Question
Find the sum of all the numbers between 3000 and 14000,
which are divisible by 25, 30 and 40.Solution
LCM of 25, 30 and 40 = 600 So, desired numbers are: 3000, 3600, …, 13800 Number of terms = (13800 – 3000)/600 + 1 = 19 Sum = (19/2) × [3000 + 13800] = 159,900
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