The Cumulative percentage polygon below shows the amount spent in dollars by 100 students at the college bookshop.

ii) Approximately how many customers spent at least $20?

iii) Approximately how much did the top 20% of customers spend?

v) What is another name for the above cumulative frequency polygon?

100 Cumulative % of students 50 0 0 20 09 80 100 40 Amount Spent ($)