Percent – a way of expressing part of a number (usually out of 100)
Ten Percent = 10 % = 10 out of 100 = 10/100
Ratio – a ratio shows the relative sizes of two or more values. It can also be described as a comparison between two or more things based on their value.
There are 10 boys and 3 girls. The ratio of boys to girls is 10:3
Rate – a specific kind of ratio, in which two measurements are related to each other.
They travelled at a rate of 55 miles per hour.
The long distance rate is $1 per minute.
The restaurant was rated highly by the food critic.