Binomial Prob passing, question, although, guess

optiix

I was thinking about this had a question

If you were to guess on every exam question (and assume that there are 4 answer choice and not 3 although we could solve it either way).

The probability of guessing 70/100 questions correct would by 100C70*.25^70*.75^(100-70).

Lets say 70% is a pass. Is the probability of passing then 100C70*.25^70*.75^(100-70) + 100C71*.25^71*.75^(100-71)+.......100C100*.25^100*.75^(100-100)?