Claim Without Certificate

hello everyone,
I am nitin. and recently i got selected for a big consulting company. in my resume i had writen that i was member of some team at college level for annual festival but do not have any certificate for it. And also a very minute calculation mistake in class X marks ( it is 85.2% but i had writen 85.4%) .
Can these things possibly result in cancellation of my offer? (specially that certificate thing)
please help!

Talk to a professor and a senior of your college and give their references in case the company asks for the certificate. Alternatively, you can get an email from a professor of your college. (I assume that you worked in the annual festival arrangement team)
For the marks it is just a typo error and you shall bring it to the HR's notice proactively.

Dear Anonymous,
These are not very huge mistakes and can be attributed to typo errors. Also in regards to the Annual Festival participation, you can tell the company, that you have no certificates but can provide references from the college to whom they can speak. Alternatively, you can visit your college and request your college to issue a letter, where the same is mentioned.
Regards,
Ashutosh Thakre

First, 85.4% is just a typo error and no company would take it seriously.
Second, you mentioned that you don't have certificate with regard to an event held at your college. Even this is not a serious one. When I was in College, even I had been part of few teams involved in organizing events, but don't have even a single certificate. So don't worry.

thanks for the prompt replies :)
actually there was no official team for it, i mean nothing on paper. My friend was organising it and i helped him publicise the event in various colleges. there might had been proper recruitments for the same but i did it unofficially and wrote it in resume.
Now what should i do?

Stay cool. It is not a big issue. No organization would insist on such certificates. In fact, most colleges do not even give certificates or appreciation letters for these.
As far as Freshers are concerned, Companies need only copies of Marksheets, Address proof and Photo proof. (For experienced candidates, employment related certificates too).
Had you been part of NCC, NSS they might ask for those certificates as some companies award points for those.
So don't worry about it.
Typo error with regard to your percentile also is not a big mistake.