Question 373163
mean=30
variance= 16
S.d = sqrt(16)= 4
using z score formula, that is 
z= xbar- mean/sigma
Z1= 26-30/4=-1
z2=34-30/4= 4/4 =1
required probability = p(26<x<34) = p(Z1)+P(z2)= 0.3413+0.3413 = 0.683 
Hence p(26<x<34)=0.683
68.3%