It's all the numbers divisible by 3 or 11 but NOT divisible by 33. Does that help?
This is a question I really don't get. I've tried all the things i can think of, and the only clue i have is: Arithmetic Sequences (this is a topic I'm horrible at).
The problem is
Find the sum of all positive integers not greater than 10000 that are divisible by either 3 or 11 but not by both of them.'
Can you please help me soon????
Tkx
Mikhael
Hello, Mikhael!
We need the formula for the sum of an arithemtic series.
The sum of the first n terms is: .
. . where: = first term, = common difference.
Find the sum of all positive integers not greater than 10000
that are divisible by either 3 or 11 but not by both of them.
Sum of multiples of 3: .
This is an arithmetic series with: .
Its sum is: .
Sum of multiples of 11: .
This is an arithmetic series with: .
Its sum is: .
Sum of multiples of 33: .
This is an arithmetic series with: .
Its sum is: .
The desired sum is: .