1. Suppose a random variable X can equal 1, 2, 3, 4, or 5. If P(X<3)=0.4 andP(X>3).
2. If Y denotes the smaller of two numbers rolled on a pair of dice, determine the probability distribution of y. If the two numbers are equal then use the common number for the value of Y.
3. A pair of dice is rolled. Find (a) the expected value of the sum of the two numbers and (b) the standard deviation of the sum.
4. Four fair dice are rolled. Find the probability that (a) the number 6 appears at least twice and (b) the number 6 appears exactly once.
I have some practice problems for an upcoming quiz and really need some help on how to do them...
1. Suppose a random variable X can equal 1, 2, 3, 4, or 5. If P(X<3)=0.4 and P(X>3)=0..5
Find P(X=3) and P(X<4).