Answer to Question #343943 in Statistics and Probability for Nics

Question

A jar contains 36 red marbles numbered 1 to 36 and 50 blue marbles numbered 1 to 50. A marble is drawn at random from the jar. Find the probability of the given event. Please enter reduced fractions.

(a) The marble is red. P(red)=

(b) The marble is odd-numbered. P(odd)=

(c) The marble is red or odd-numbered. P(red or odd) =

(d) The marble is blue or even-numbered. P(blue or even)

Answer 1

(a)

$$P(red)=\dfrac{36}{36+50}=\dfrac{18}{43}$$

(b)

$$P(odd)=\dfrac{36/2+50/2}{30+56}=\dfrac{1}{2}$$

(c)

$$P(red\ or\ odd)=\dfrac{36+50/2}{30+56}=\dfrac{61}{86}$$

(d)

$$P(blue\ or\ even)=\dfrac{36/2+50}{30+56}=\dfrac{34}{43}$$