This question came up on an exam I had on Monday and I answered it but I won’t be getting the test back for a while and I’m really anxious to see if I got it correct.

Could you guys please help me with the **second part of this question.**

The questions state as follows:

4.A.

fully expand (p+q)^5

I have done this, using the binomial expansion theorem and have gotten an answer of:

p^5 +5p^4q + 10p^3q^2 + 10p^2q^3 + 5pq^4 + q^5

**B.**

**a fair 4 sided die, numbered 1, 2, 3, and 4, is rolled 5 times. Let p represent the probability that the number 4 is rolled on a given roll, and let q represent the probability that the number 4 is not rolled on a given roll.**

**Using the first 3 terms of the binomial expansion from part a, find the probability that the number 4 is rolled at least 3 times.**

How do I answer part B?

Thank you