Math

• A ratio is a comparison of two or more quantities with the same unit.
• Ratio can be written in three different ways.

  Using a colon - 1:3

  Using the word “to” - 1:3

  Using a fraction - 1/3
• We can use scale factors to identify equivalent ratios
• A proportion is a number sentence that shows to equivalent ratios
• We use scale factors ( numbers that are multiplied or divided by each term in a ratio) proportions
• We can find missing terms and proportions by cross multiplying
• A rate is a comparison of two quantities measured in different types of units. Example speed.
• A unit rate is right in which the second value is 1.

  example, a car travels 100 km in 2 hours = 50 km an hour
• We can find the unit rate by dividing one term by another

  type 120 words in 3 minutes

  120/3 mins

  40 w/m = 40wpm
• An equivalent rate is a rate that makes the same comparison
• Ratios can be part to part

  the ratio of girls to boys is 3:1

  Ratios can be part to whole

  the ratio of girls to everyone 3:4