Answer:
x = - 6
Step-by-step explanation:
Given that y varies directly as x then the equation relating them is
y = kx ← k is the constant of variation
To find k use the condition y = - 9 when x = 3, thus
k = =
= - 3
y = - 3x ← equation of variation
When y = 18, then
18 = - 3x ( divide both sides by - 3 )
x = - 6
Answer:
(a) 0.20
(b) 31%
(c) 2.52 seconds
Step-by-step explanation:
The random variable <em>Y</em> models the amount of time the subject has to wait for the light to flash.
The density curve represents that of an Uniform distribution with parameters <em>a</em> = 1 and <em>b</em> = 5.
So,
(a)
The area under the density curve is always 1.
The length is 5 units.
Compute the height as follows:
Thus, the height of the density curve is 0.20.
(b)
Compute the value of P (Y > 3.75) as follows:
Thus, the light will flash more than 3.75 seconds after the subject clicks "Start" 31% of the times.
(c)
Compute the 38th percentile as follows:
Thus, the 38th percentile is 2.52 seconds.