Let's use this question to discuss on drawing and using cumulative frequency curve.

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(a) Drawing of cumulative freq curve

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**Step by step solutions:**

**Notes:**

140 pupils weigh 72.5 kg *or less. *So if you are interested to find out the number of pupils who weigh more than 72.5 kg. It will be 280 (total number of pupils) - 140 = 140 pupils.

Special attention to (iii) no. of students who weigh more than 65kg. By going UP & ACROSS, we get 20 students. This only means 20 students weigh 65 kg *or less. *So the rest (280 - 20 = 260) will weigh more than 65 kg

In my next post, I will be discussing the features of box and whisker plot.