Refer to the following distribution of commissions. Monthly Commissions Class Frequencies $600 up to $800 3 800 up to 1,000 7 1,000 up to 1,200 11 1,200 up to 1,400 12 1,400 up to 1,600 40 1,600 up to 1,800 24 1,800 up to 2,000 9 2,000 up to 2,200 4

What is the class interval?

3,500

200

300

400