here n=200, mean=3.4, SE=2.2 ( I think this is standard deviation (SD) ans wrongly wrote SE)
(question is attempted on the assumption that it is SD, if not please respond back at earliest)
we use standard normal variate Z=(X-mean)/SD
for x=3.5, z=(3.5-3.4)/2.2=0.0455
for x=4.5, z=(4.5-3.4)/2.2=0.5
P(3.5<X<4.5)=P(0.0455<Z<0.5)=P(Z<0.5)-P(Z<0.0455)=0.6915-0.5181=0.1733
required number=n*P(3.5<X<4.5)=200*0.1733=34.66 ( next whole number is 35)
answer is 35
trd tsfolhs 200 Lal op accovlng ffatey af 3.4 an SE f2.2 ow Man f- thest...
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