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Use binomial Coefficient (53) in first box, you can use the two brackets as they are in the list. This equals 10 + 5 + 15 = 30.

There is no solution. If you could use decimals then 7.5+7.5+15=30, but without decimals I do not see how there is a solution.

It was solved once, so there is an answer! lets see who comes out correct...

The other comment is correct. You simply canNOT add odd numbers together and get an even number... ever.

You CAN, however, answer the question using 'tricks'. One of which (mentioned by knowledge-seeker) is to use decimals. There are at LEAST four other ways. Best written explanation I found:

https://www.quora.com/Mathematical-Puzzles-What-is-+-+-30-using-1-3-5-7-9-11-13-15

So.... I guess the winner would depend on which trick they used (so as to match Gaurav Agarwal's answer).

Cheerio!