Lou has a box containing some yellow sweets and some pink sweets.

Lou could select a sweet at random, note its colour, put it back and then select a sweet again. Alternatively, Lou could select a sweet at random, eat it, and then select a second sweet.

The probability that both sweets chosen are yellow is 10% greater for the first option than for the second option. 

What is the largest number of sweets that could be in the box?

Note: there are at least two yellow sweets in the box!