Education.com
Try
Brainzy
Try
Plus

Using Algebra in Statistics and Probability Study Guide (page 3)

based on 1 rating
By
Updated on Oct 3, 2011

Example

The gumball machine contains 12 red gumballs, 8 green gumballs, 5 yellow gumballs, and 7 orange gumballs. How many green gumballs must be added to make the probability of selecting a green gumball ?

The probability of selecting a green gumball is equal to the number of green gumballs divided by the total number of gumballs. Let x represent the number of green gumballs added to the machine. That means there are now 8 + x green gumballs, and 12 + 8 + 5 + 7 + x = 32 + x total gumballs. The probability of selecting a green gumball is equal to . The value of x will make this probability equal to , so set the two fractions equal to each other and solve for x:

      =

Cross multiply:

      2(8 + x) = 32 + x
      16 + 2x = 32 + x
      16 + x = 32
      x = 16

For the probability of selecting a green gumball to become , 16 green gumballs must be added to the gumball machine.

Find practice problems and solutions for these concepts at Using Algebra in Statistics and Probability Practice Questions.

View Full Article
Add your own comment