ratio and proportion notes

ratios

reducing ratios to their simplest form

• divide all the numbers in the ratio by the same thing
• it's in its simplest form when there's nothing left you can divide by

if the ratio contain decimals or fractions- multiply

• with decimals, multiply both sides by a power of 10 to get rid of the decimal parts
• divide to reduce the ratio to its simplest form
• with fractions, put them over a common denominator
• multiply both sides by the denominator
• divide to reduce the ratio to its simplest form

if the ratio has mixed units- convert to the smaller unit

to get the form 1:n or n:1- divide

scaling up ratios

• if you know the ratio between parts and the actual size of one…