Final answer:
Ricky's rate was $0.25 more per hour than Susan's rate. Therefore, the correct option is D.
Step-by-step explanation:
To compare Susan's and Ricky's rates, we need to calculate how much they earned per hour of work.
Susan earned $27 for 6 hours of work, so her rate would be $27 divided by 6 hours, which is $4.50 per hour.
Ricky earned $14.25 for 3 hours of work, so his rate would be $14.25 divided by 3 hours, which is $4.75 per hour.
Based on these calculations, the statement that is true about their rates is: d) Ricky's rate was $0.25 more per hour.