Ratio and Proportion

A Ratio tells us how much of one thing there is compared to another

Recipes (100ml flour to 1 part salt)

Mixing drinks (1 part cordial to 6 parts water) Building (4 parts sand to 1 part cement)

Maps (1cm to 1km/mile)

Plans (scale drawings)

Infection Rates (1 person may infect 1.5 other people, etc) (COVID-19)

Add the Ratio Numbers up (3:1 3+1 = 4)

Divide $240 by 4 = $60

Why four?

Multiply each part of the ratio by $60

Why 60?

3 x 60 = 180, and 1 x 60 = 60 Check the amounts add up correctly ($180 + $60 = $240)