Exercise 4 Page 772

When calculating a probability, we are comparing the number of favorable outcomes to the number of possible outcomes. To calculate the probability of obtaining a number not greater than 4 when rolling a number cube, we will use the Probability Formula. P=Favorable Outcomes/Possible Outcomes On the number cube there are 6 numbers. This is the number of possible outcomes. 1, 2, 3, 4, 5, 6 Furthermore, there are 4 numbers that are not greater than 4. This is the number of favorable outcomes. 1, 2, 3, 4, 5, 6 Now we have enough information to calculate P(Not greater than4).

P=Favorable Outcomes/Possible Outcomes

SubstituteValues

Substitute values

P(Not greater than4)=4/6

ReduceFrac

a/b=.a /2./.b /2.

P(Not greater than4)=2/3

The probability of rolling a number not greater than 4 on the cube is 23, which can also be written as 2:3.