Notice: five groups, all of the same width. There are no gaps – every length from 30 to 55 can be recorded. There are no overlaps between the groups – eg the inequality symbols show that exactly 35 cm ...

Notice: five groups, all of the same width. There are no gaps – every length from 30 to 55 can be recorded. There are no overlaps between the groups, eg the inequality symbols show that exactly 35 cm ...