A box is filled with 9 red crayons, 2 blue crayons, and 5 yellow crayons. A crayon is chosen at random from the box. Find the probability that it is a red or a blue crayon. Write your answer as a fraction in simplest form.

Respuesta :

Answer:

[tex]P(Red\ or\ Blue) = \frac{11}{16}[/tex]

Step-by-step explanation:

Given

[tex]Red = 9[/tex]

[tex]Blue = 2[/tex]

[tex]Yellow = 5[/tex]

Required

Probability of Red or Blue

First, it should be noted that the event described in the question are mutually exclusive or disjoint events;

Meaning that the probability of one have no effect the other;

Having said that; the Probability of Red ot Blue is as follows

[tex]P(Red\ or\ Blue) = P(Red) + P(Blue)[/tex]

Calculating [tex]P(Blue)[/tex]

[tex]P(Blue) = Number\ of\ blue\ crayon / total\ crayon[/tex]

[tex]P(Blue) = \frac{2}{9+ 2 + 5}[/tex]

[tex]P(Blue) = \frac{2}{16}[/tex]

Calculating [tex]P(Red)[/tex]

[tex]P(Red) = Number\ of\ red\ crayon / total\ crayon[/tex]

[tex]P(Red) = \frac{9}{9+ 2 + 5}[/tex]

[tex]P(Red) = \frac{9}{16}[/tex]

Substitute these values in the formula given above

[tex]P(Red\ or\ Blue) = P(Red) + P(Blue)[/tex]

[tex]P(Red\ or\ Blue) = \frac{9}{16} + \frac{2}{16}[/tex]

Take LCM

[tex]P(Red\ or\ Blue) = \frac{9 + 2}{16}[/tex]

[tex]P(Red\ or\ Blue) = \frac{11}{16}[/tex]

Hence, the probability of a red or blue crayon is

[tex]P(Red\ or\ Blue) = \frac{11}{16}[/tex]