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 can be written in several different ways. 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 1/8 Compare octagon to all shapes 1 out of 8 1 : 8

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

Ratios and Rates Compare pentagons to hexagons 2/3 2 to 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 miles 79 miles per hour = hours hours

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