SOLUTION: Find the sum of the multiples of 6 greater than or equal to 48 but less than 295

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Question 1086737: Find the sum of the multiples of 6 greater than or equal to 48 but less than 295
Answer by Edwin McCravy(20060) About Me  (Show Source):
You can put this solution on YOUR website!
48 is a multiple of 6, so it's the first term

295/6 = 49.16667, so the largest multiple of 6 less than
295 is 6 times the whole part of 49.16667 which is 49.
That's 6*49 or  294.

a%5Bn%5D=a%5B1%5D%2B%28n-1%29d
294=48%2B%28n-1%296
294=48%2B%28n-1%296
246=6%28n-1%29
Divide both sides by 6
41=n-1%29
42=n

S%5Bn%5D=expr%28n%2F2%29%28a%5B1%5D%2Ba%5Bn%5D%29
S%5B42%5D=expr%2842%2F2%29%2848%2B294%29
S%5B42%5D=21%28342%29
S%5B42%5D=7182

Edwin