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 ...

Frequency tables can be used to help present sets of data. There are 4 children aged 10, which gives a total age of 40 in that category. There are 6 children aged 11, which gives a total age of 66 in ...