# Ratios and Rates Ratios and Rates ratio a

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Ratios and Rates

Ratios and Rates ratio – a comparison of two numbers by division written in several different forms.

Ratios and Rates rate – a ratio that compares different kinds of units by division to obtain a unit rate or rate per unit.

Ratios and Rates The order of the numbers in a ratio should match the order of the words in a ratio. apples to oranges 2 to 3

Ratios and Rates Ratios can be written in several different ways. red to white 3 to 1 3: 1 3/1

Ratios and Rates Ratios can show comparisons between: part to part red to green 1 to 2 green to red 2 to 1

Ratios and Rates Ratios can show comparisons between: part to whole red to whole 1 to 3 green to whole 2 to 3

Ratios and Rates Ratios can show comparisons between: whole to part whole to red 3 to 1 whole to green 3 to 2

Ratios and Rates Compare octagon to all shapes 1 out of 8 1 to 8 1: 8 1/8

Ratios and Rates Compare all shapes to trapezoid 8 to 1 8: 1 8/1

Ratios and Rates Compare pentagons to hexagons 2 to 3 2: 3 2/3

Ratios and Rates Give each ratio in three forms. 8 roses out of 24 flowers 8 to 24 8 : 24 3 dogs out of 12 animals 3 to 12 3 : 12

Ratios and Rates A ratio in fraction form can be expressed in simplest form by dividing the numerator and denominator by a common factor. ÷ 8 ÷ 3 = ÷ 8 = ÷ 3

Ratios and Rates To express a ratio as a rate per unit, write the ratio as a fraction and then divide the numerator by the denominator. 395 miles in 5 hours miles = hours miles 79 miles hours per hour

Ratios and Rates Express each ratio as a rate. 5 inches of rain in 30 days ÷ 5 = ÷ 5 inch of rain per day 120 words in 3 minutes = 40 words per minute