Answer:
7
Step-by-step explanation:
σ = 4 ; μ =?
8.52 to the left of X
.
P(X < 8.52) = 64.8%
P(X < 8.52) = 0.648
Using the Z relation :
(x - μ) / σ
P(Z < (8.52 - μ) / 4)) = 0.648
The Z value of 0.648 of the lower tail is equal to 0.38 (Z probability calculator)
Z = 8.52 - μ / 4
0.38 = 8.52 - μ / 4
0.38 * 4 = 8.52 - μ
1.52 = 8.52 - μ
μ = 8.52 - 1.52
μ = 7
32.6 0.61
+3.54 x 0.45
--------- ----------
36.14 305
+ 2440
Answer:
x=8
Step-by-step explanation:
the y-value in the first pair decreased by half, so the x-value must double due to inverse variation.
(5/10)*(4/9)=20/90 which reduces to 2/9 which is B