Answer:
0.0062
Step-by-step explanation:
Find the standard error.
σ = 20 / √100
σ = 2
Find the z-score.
z = (x − μ) / σ
z = (70 − 65) / 2
z = 2.5
Find the probability.
P(Z > 2.5) = 1 − 0.9938
P(Z > 2.5) = 0.0062
Z = x-y(3r)/y
z = x-y * 3r/y
Final answer: x = yz + 3yr
Answer:
Known two points, list function expression, use


The function expression is

It is known that the cross section of two points is 7, so the point of 2:3 is 14 / 5, that is, 0 + 14 / 5 is the abscissa of the point, which is substituted into the original equation to get y = - 7 / 5.
So the result is 
Answer:
3.6
Step-by-step explanation:
So, 1/3 of the posters were not originally posted. Then, 1/5 of the remaining 1/3 were not posted. So, 1/5 of 1/3 is 1/15. 54/15 = 3.6.