Frequency question?

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2 Answers
Jan 10, 2018

#20.2%(1dp)#

Explanation:

For a histogram it is the AREA of the bars that measures the actual frequency.

So the first task is to calculate the frequency for each interval

Total#=10xx6+10xx17.5+20xx13+5xx15+10xx5#

#=60+175+260+75+50#

#=620#

Those over #40=75+50#

#=125#

#:% "over 40"=125/620xx100#

#=20.2%(1dp)#

Jan 11, 2018

see below

Explanation:

enter image source here

to explain the last part more clearly:

the data has been put into a table

we need the % of visitors over 40.

from the table we see that the last two rows of the data give us those over 40

namely

#40-45rarr75" visitors"#

#45-55rarr50" visitors"#

so the total number of visitors over 40 #=75+50=125#

to find the % over 40 we compare this with the total and multiply by 100 to

#125/620 xx100#

#=20.2%#