Exercise 18 Page 717

When calculating probability, we are comparing the number of favorable outcomes to the number of possible outcomes. To calculate the probability that a randomly chosen card has a number that is not multiple of 4 we will use the Probability Formula. P=Favorable Outcomes/Possible Outcomes There is a total of 10 cards socks, which is the number of possible outcomes. 1,2,3, 4,5,6,7, 8,9,10Out of ten cards, there are eight cards that are not multiple of 4. This means that the number of favorable outcomes is 8. Now we have enough information to calculate P(not multiple of4).

P=Favorable Outcomes/Possible Outcomes

SubstituteValues

Substitute values

P(not multiple of4)=8/10

ReduceFrac

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

P(not multiple of4)=8/2/10/2

CalcQuot

Calculate quotient

P(not multiple of4)=4/5

The probability of choosing a card with a number that is not a multiple of 4 is 45. Next, we can rewrite the fraction as a decimal and as a percent.

As a Decimal

To write a fraction as a decimal, we divide the numerator by the denominator.

We found that 45 expressed as a decimal is 0.8.

As a Percent

To write a fraction as a percent, we first find an equivalent fraction with a denominator of 100. 4/5=p/100 Let's solve the equation for p.

4/5 = p/100

MultEqn

LHS * 100=RHS* 100

4/5* 100 =p/100* 100

FracMultDenomToNumber

a/100* 100 = a

4/5* 100 = p

MoveRightFacToNumOne

1/b* a = a/b

400/5 = p

CalcQuot

Calculate quotient

80 = p

RearrangeEqn

Rearrange equation

p = 80

The fraction written as a percent is 80 %.