©2009 – Not to be sold/Free to use Stage 5 Year 9 Rational Numbers Rates Press Ctrl-A ©2009 – Not to be sold/Free to use

A Rate is a comparison of two unlike quantities Rates A Rate is a comparison of two unlike quantities e.g. 60 km /h  Distance  Time e.g. $12 for 8 kg  Money  Mass e.g. 5000kg in 10 L  Mass  Capacity (Volume) 2

Rates - Simplifying Example 1: $300 in 6 hours   Divide the 1st number  by the 2nd number. = 300  6 = $50/h Example 2: 1000 kg in 5 minutes  Divide the 1st number  by the 2nd number. = 1000  5 = 200 kg/min 3

Rates - Converting Example 3: Convert 48 kg/day to kg/h  1 day = 24 hours = 48 kg in 24 hours = 48  24 = 2 kg/h Example 4: Convert $3/min to $/h  1 hour = 60 minutes = $3 per 1 min = $(3 x 60) per (1 x 60) min = $180 per 60 min = $180/h 4