A comparison of two related quantities.
Often written "this per that" but there are many possibilities, including a single number calculated using division.
Example: Sam makes 3 pancakes every 6 minutes, that is a rate of:
• 3 pancakes per 6 minutes
• 0.5 pancakes per minute
• 30 pancakes per hour
• an hourly rate of 30
• etc
Example: 200 sausages were eaten by 50 people. that is:
• 200 sausages per 50 people
• 100 sausages per 25 people
• 4 sausages per person
Example: Alex invested $100 for a month and made $3
• the interest rate is 3/100 = 3% per month
When we compare to a single unit quantity we call it a Unit Rate.
See: Unit Rate