Question 6 - A-Level Maths

Exam Board	CAIE
Module	S1 (Statistics 1)
Year	2013
Session	June
Topic	Data representation
Type	Draw cumulative frequency graph from cumulative frequency table

6 The weights, \(x\) kilograms, of 144 people were recorded. The results are summarised in the cumulative frequency table below.

Weight \(( x\) kilograms \()\)	\(x < 40\)	\(x < 50\)	\(x < 60\)	\(x < 65\)	\(x < 70\)	\(x < 90\)
Cumulative frequency	0	12	34	64	92	144

On graph paper, draw a cumulative frequency graph to represent these results.
64 people weigh more than \(c \mathrm {~kg}\). Use your graph to find the value of \(c\).
Calculate estimates of the mean and standard deviation of the weights.