The answer I believe is 5 because 2 vases hold 10 red roses and 5 yellow roses. But since the person has 3 vases but it has to be the same amount as the first person. They would both have 30 flowers in their vases. But then each of the vases has 6 red roses so you just do 30 divided by 6 and you get 5.
The pattern
5 10 3 15 20 13 25 30....
the next number is
23 because after each 2 numbers its +10
Hope this helps,
xXharleyquinn04Xx
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