Math Practice Online > free > lessons > Florida > 9th grade > Object Picking Probability

Here are some tips for Object Picking Probability, which aligns with Florida state standards:

Object Picking Probability

To review the basics of probability, see here.
To review the probability of multiple events, see here.

In this topic, you will practice calculating the probability of multiple events related to picking objects out of a bag.

Quick review:

 Probability of an event = P(event) =
Probability of 2 events happening: P(event1 and event2) = P(event1) × P(event2)

Example 1: Placing the object back

A bag contains 8 coins: 4 pennies, 3 nickels, and 1 dime. If you take one coin out, put it back, and take another coin out, what is the probability that you'll get 1 dime followed by 1 nickel?

Since the first coin is placed back in the bag, the total number of possible outcomes for each coin picking event is the same.
P(picking 1 dime followed by 1 nickel) = P(picking 1 dime) × P(picking 1 nickel)
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Example 2: Without placing the object back

A bag contains 6 jelly beans: 3 red jelly beans, 2 yellow jelly beans, and 1 blue jelly bean. If you take one jelly bean out, don't put it back, and take another jelly bean out, what is the probability that you'll get 1 red jelly bean followed by 1 yellow jelly bean?

Since the first jelly bean is not placed back in the bag, the total number of outcomes for the second pick is 1 less than the total number of outcomes for the first pick.
P(picking 1 red jelly bean followed
by 1 yellow jelly bean)
= P(picking 1 red jelly bean) × P(picking 1 yellow jelly bean)
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