Suppose a coin is tossed 21 times in a row with equal probability of heads and tails
a. What is the probability that heads does not occur three times in a row?
That is, with 21 tosses, what is the probability heads is never immediately
followed by two other heads?

b. What is the probability that the coin is facing the same way three times in
a row (that is three heads in a row or three tails in a row) exactly once in
the 21 tosses?

According to the 2008 u.s. census, california had a population of approximately 4 × 10^7 people and florida had a population of approximately 2 × 10^7 people. which of the following is true? a. the population of florida was approximately two times the population of california. b. the population of florida was approximately twenty times the population of california. c. the population of california was approximately twenty times the population of florida. d. the population of california was approximately two times the population of florida.

Solve the equation by completing the square. x^2+2x=17

Amira is painting a rectangular banner 2 1/4 yards wide. the banner will have a blue background. amira has enough paint to cover 1 1/2 square yards of the wall. the school colors are blue and yellow, so amira wants to add yellow rectangles on the left and right sides of the blue rectangle. the yellow rectangles will each be 3/4 yards wide and the same height as the blue rectangle. what will be the total area of the two yellow rectangles?