Scarlett selects a card at random from a deck that contains 18 red, 12 yellow, and 20 blue cards. What is the probability that she does not select a red card?

Answer 1

Hello Bayne,

You can find the answer a couple of ways:

Option 1: find the probability that she DOES select red: p(red) = (number of RED)/total number = 18/(18+12+20) = 18/50 = 9/25

Then you subtract it from 1 to find the probability she DOES NOT select red:

P(NOT red) = 1 - 9/25 = 25/25 - 9/25 = 16/25

-------

Option 2: if Scarlett does not select red, it means she will select other colors that are in the deck: yellow or blue.

probability that she doesn't choose red is the SAME as the probability she picks yellow or blue:

p(not RED) = p(YELLOW or BLUE) = (number of YELLOW + number of BLUE) / total = (12+20)/50 = 32/50 = 16/25