Answer:
Step-by-step explanation:
We know that when X is normal
X-mu/sigma is std normal
Here the scores X is normal with mean =140 and sd =40
a) X=172
gives Z = 32/40 = 0.80
P(Z<0.8) = 0.5+0.2881
=0.7881
Hence 79th percentile
b) X =200 then x-mu = 60
So z=60/40 = 1.5
c) 100<x<160 means
1.5<z<0.5
d) X>190 means Z>1.25 hence proportion = P(Z>1.25) =0.5-0.3944
=0.1056
e) For 67th percentile z value = 0.0675
Hence x score = 140+0.0675(40) = 142.7
An=a*q^(n-1)
a7=a*q^6
a7=4096*(1/2)^6=4096/32=128
Answer:
It would take around <u>5</u><u> </u><u>Days</u>
