Answer:
x = - 3 ±
Step-by-step explanation:
Given
4x² + 24x = 4 ( divide through by 4 )
x² + 6x = 1
To complete the square
add ( half the coefficient of the x- term )² to both sides
x² + 2(3)x + 9 = 1 + 9
(x + 3)² = 10 ( take the square root of both sides )
x + 3 = ± ( subtract 3 from both sides )
x = - 3 ±
Answer:
And using this formula we have this:
Then we can conclude that the probability that that a person waits fewer than 11 minutes is approximately 0.917
Step-by-step explanation:
Let X the random variable of interest that a woman must wait for a cab"the amount of time in minutes " and we know that the distribution for this random variable is given by:
And we want to find the following probability:
And for this case we can use the cumulative distribution function given by:
And using this formula we have this:
Then we can conclude that the probability that that a person waits fewer than 11 minutes is approximately 0.917