For some number , there are red marbles and blue marbles in the bag.
So the total number of marbles is .
This means that the total number of marbles can be any multiple of 7. (Note that for other cases, you would need to reduce the ratio to lowest terms and then use this method.)
When we add up all the numbers we get 111 then we divide it by 10 which gives us 11.1. since we have no value to round to the tenths place, the answer stays the same.
