Question 1194427
variance is 100; sd is sqrt(100) or 10
sample sd is 10/sqrt(n)=2
to get a probability of 0.8 in the middle of the normal curve is z=-1.28 to z=+1.28
z*SE is the interval, so the interval is +/-1.28*2, or 2.56 with is added to and subtracted from 190 to get the interval.
the interval is (187.44, 192.56) whatever the weight units are, probably pounds.