1.In solving for the 60th percentile,the lower boundary is

answer:23.5

explanation:
60th percentile=formula

first find:kn/100= k=60, n=40

60(40)/100=2400/100=24
class interval score= 24-27 cf=21

apply formula:
60th percentile=LB+[(kn/100-Cf)/f]×i
LB=23.5
kn=24
Cf=21
f=7
i=4

60th percentile=23.5+[(24-21)/7]×4
=23.5+[3/7]×4
=23.5+0.4286×4
60th percentile=25.21


Formula:
Pk=LB+[(kn/100-Cf)÷f]×cw

Percentile=x or the one u looking for
LB=lower bounderies
Cf<=less than cumulative frequency
f=frequency of the class
i=interval
n=total of all frequency

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