:8. Solution. The units on the horizontal line are in hundreds
of jelly beans.  The class interval 3-5, representing people who
reported consuming <p>

a. at least 300 but no more than 400 jelly beans  <p>

b. at least 400 but no more than 500 jelly beans, <p>

is two units long. The rectangle with base equal to this class
interval should be 20%, so its height should be 20/2 = 10 percent
per unit. <p>