Probability that next marble is not red is 0.75
Solution:
Given that bag of marbles contains blue (B), red (R), yellow (Y), and green (G) marbles.
A marble is drawn from the bag, recorded, and then placed back in the bag. To find: the probability the next marble is NOT red
The probability of an event is given as:
![probability =\frac{\text { number of favorable outcomes }}{\text { total number of possible outcomes }}$](https://img.qammunity.org/2020/formulas/mathematics/high-school/i9c5friyhx5pnf2f645ak8wxq2a4qww3ba.png)
Let us first find the probability of getting red marble
Total number of possible outcomes = blue + red + yellow + green
Total number of possible outcomes = 4
Favorable outcome = getting red marble
Number of favorable outcomes = 1
![P(R) = (1)/(4)](https://img.qammunity.org/2020/formulas/mathematics/college/bi85ly1k0e5uduspn3onhnmgo38rz13g2x.png)
Finding probability that next marble is NOT red:
P( NOT R) = 1 - P(R)
![\text{ P( NOT R) } = 1 - (1)/(4) = (4 - 1)/(4) = (3)/(4) = 0.75](https://img.qammunity.org/2020/formulas/mathematics/college/7fkqigwtemwtdx83j28myt7yv2ezabd0ou.png)
Thus probability that next marble is not red is 0.75