Ratios and Rates

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Ratios and Rates
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What is a ratio?

• A ratio is a comparison of two numbers by
  division.
• The ratio of the number 2 to the number 3 can be
  written in these three ways
• 2 to 3, 23, or 2/3.
• Ratios are often expressed as fractions in
  simplest form or as decimals.

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Time for practice!

• Express each ratio or rate as a fraction in the
  simplest form.
• 1035
• 6020
• 3 to 39
• 8 out of 14
• 18 boys to 15 girls
• 16 blue to 4 green

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What is a rate?

• A rate is a special ratio that compares two
  measurements with different units of measure,
  such as miles per gallon or cents per pound.
• A rate with a denominator of 1 is called a unit
  rate.

5
Time for Practice!

• Express each ratio as a unit rate.
• 294 miles on 10 gallons
• 0.72 for 12 ounces
• 3.88 for 2 pounds
• 3.4 inches of rain in 2 months
• 200 meters in 23.5 seconds
• 21 for a half dozen roses

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Find the following ratios by polling students in
our classroom

• Boys vs. girls in the classroom
• Brown eyes vs. blue/green eyes
• Students who like math vs. those who do not
• Students wearing jeans vs. another type of
  pant/shorts
• Students with pierced ears vs. not pierced