The table shows the marks that a class of students received in a mathematics test. How many students got less than 45 marks?
The number of marks have been split into groups. Those that represent students that got less than 45 marks are 20 to 24, 25 to 29, 30 to 34, 35 to 39, and 40 to 44. This means that we need to add these five frequencies. We need to add seven, eight, two, five, and six. Adding these five numbers gives us a total of 28. We can therefore say that 28 out of the 44 students got a mark of less than 45 in the mathematics test.
This means that 16 students scored 45 marks or more. We can check this by adding five, nine, and two. Five plus nine is equal to 14. And adding two gives us 16.
This means that our original answer of 28 students is correct.