SOLUTION: find the sum of all integers that are multiple of 4 from 1 to 150

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Question 1118805: find the sum of all integers that are multiple of 4 from 1 to 150
Answer by htmentor(1343) About Me  (Show Source):
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This is an arithmetic sequence, with the common difference equal to 4 and the first term equal to 4.
The n-th term is given by a_n = 4 + 4(n-1) which simplifies to a_n = 4n
The last term divisible by 4 is 148, thus n = 37
The sum of n terms of an arithmetic sequence is S_n = (n/2)*(a + a_n)
S_n = (37/2)*(4+148) = 2812