a To determine probability, we divide the number of favorable outcomes with the number of possible outcomes.
B
b This time, you want to find the number of possible outcomes.
A
a 60 %
B
b 60
Practice makes perfect
a To determine probability, we divide the number of favorable outcomes with the number of possible outcomes.
P=Number of favorable outcomes/Number of possible outcomesFrom the exercise, we know that the tank contains 9 spotted guppies, 14 red barbs, 10 red tetras and 7 golden platys. If we add the number of fishes in the tank, we get the total number of possible outcomes.
9+14+10+7=40
We are looking for the probability of getting a red-colored fish. Assuming that only fish with the word "red" in their name are red, we have 14+10=24 favorable outcomes. With this, we can calculate the probability of picking a red-colored fish.
P=Number of favorable outcomes/Number of possible outcomes
The probability of picking a red-colored fish is 60 %.
b We want to find the number of possible outcomes, which we will call x. By substituting the probability of getting a female fish, as well as the number of females in the tank, 18, we can solve for the number of possible outcomes, x.
P=Number of favorable outcomes/Number of possible outcomes
