Help with binomial distribution

for each question, there's a 1/5 chance to get it right. the chance you'll get 3 right is 1/125, 4 right is 1/625, 5 right is 1/3125, 5 right is 1/15625, and 6 right is 1/78125. Add those together and you'll get 0.0099968. 

 

I think that's how you do it, but I could be wrong since I haven't done these in a while

It'll be 1- P (exactly 0,1 or 2 correct)

P(0)=0.8^6

P(1)=6C1×0.2×0.8^5

P (2)=6C2×0.2^2×0.8^4

Add those together and subtract the answer from 1.