A company has 50 employees all working in the same building.
As part of their safety procedures, a fire drill is carried out with the total number
of employees who have left the building recorded every 10 seconds.
The results are displayed in the cumulative frequency diagram below.
The company has the following
policy: "In the event of a fire, at least
90% of the employees must have
left the building within 1 minute."
Cumulative frequency
Did the fire drill procedure meet the
policy above?
You must show all your working.
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