PREREQUISITE SKILLSON RATIOS

IN THE REAL WORLD

Baseball  How can you compare a baseball team’s wins to its losses during spring training?

A ratio uses division to compare two numbers. There are three ways to write a ratio of two numbers.

WRITING A RATIO

All three ways of writing the ratio of two numbers are read “the ratio of a to b,” so 18 : 13 is read “the ratio of eighteen to thirteen.” Two ratios are equivalent ratios when they have the same value.

EXAMPLE 1 WRITING A RATIO 1. You can make comparisons about games played

by the Cubs.

a. Wins to losses

wins = 17, losses = 14 Answer: _______

b. Wins to games played

wins = 17, games = 17 + 14 = 31 Answer: _________

YOUR TURN

Use the table above to write the ratio for the Padres.

1. Wins to losses2. Wins to games played3. Losses to wins

EXAMPLE 2 WRITING RATIOS IN SIMPLEST FORM Amusement Parks  A ride on a roller coaster lasts 2 minutes.

Suppose you wait in line for 1 ½ hours to ride the roller coaster. Follow the steps below to find the ratio of time spent in line to time spent on the ride.

-Write hours as minutes so that the units are the same.

-Write the ratio of time spent in line to time spent on the ride.

EXAMPLE 3 COMPARING RATIOS

Music:  Luis and Amber compared their CD collections. To determine who has a greater ratio of rock CDs to pop CDs, write the ratios.

1. Write ratios as fractions (rock/pop).2. Write fractions as decimals and compare.

Luis:

Amber:

YOUR TURN

1. Does Luis or Amber have a greater ratio of pop CDs to hip-hop CDs?

2. Does Luis or Amber have a greater ratio of hip-hop CDs to rock CDs?