Daaaaaaaaaammmmm that’s hard
We have
mean=mu=170
standard deviation=sigma=5
can now calculate the Zmin and Zmax using Z=(X-mean)/standard deviation
Zmin=(165-170)/5=-1
Zmax=(175-170)/5=+1
From normal probability tables,
P(z<Zmin)=P(z<-1)=0.15866
P(z<Zmax)=P(z<+1)=0.84134
P(165<x<175)=P(Zmin<z<Zmax)=0.84134-0.15866= 0.68269
Answer:
The answer is (B)
Step-by-step explanation:
Try out each of the situations. It can't be A, since the 0.9 is less than 1, so it has to be decreasing. This leaves only B and C. Since decreasing by 90 percent is the same as multiplying by 10 percent, the only possible answer left is B.
Hope this helps!