7th Grade Math

Lesson 1C Probability 441

JEANS The Jeans Shop

sells young men’s jeans in

different sizes, styles, and

lengths. Find the number of

jeans available. Then find

the probability of randomly

selecting a size 32 × 34

slim fit. Is it likely or

unlikely that the size would

be chosen?

size length style total

··=

Fundamental Counting

Principle

There are 45 different types of jeans to choose from. Out of the

45 possible outcomes, only one is favorable. So, the probability of

randomly selecting a 32 × 34 slim fit is _^1

45

or about 2%.

It is very unlikely that the size would be chosen at random.

b. JEANS If the Jeans Shop adds relaxed fit jeans to its selection,

find the number of available jeans. Then find the probability

of randomly selecting a 36 × 30 relaxed fit pair of jeans. Is it

likely or unlikely that the size would be chosen?

The Jeans Shop

Waist Size Length (in.) Style

30 30 slim fit

32 32 bootcut

34 34 loose fit

36

38

Jean Size Jean Size In men’s jeans,

the size is labeled waist x

length. So, a 32 x 34 is a

32-inch waist with a

34-inch length.

Use the Fundamental Counting Principle to find the

total number of outcomes for each situation.

Example 1

11 tossing a quarter, a dime, and a nickel

2. choosing a number on a number cube and
   picking a marble from the bag at the right

Example 2 3. CLOTHES Mira has 3 sweaters, 4 blouses, and

6 skirts that coordinate. Find the number of

different outfits consisting of a sweater, blouse,

and skirt that are possible. Then find the probability

of randomly selecting a particular sweater-blouse-skirt

outfit. State the probability as a fraction and percent. Is the probability of

this event likely or unlikely?

y

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