7/10 - 1/4 use common denominators
28/40 - 10/40 = 18/40 = 9/20
Answer:
No real roots
Step-by-step explanation:
Given
7x² + 5x + 1 = 0 ← in standard form
with a = 7, b = 5, c = 1
To determine the nature of the roots use the discriminant
Δ = b² - 4ac
• If b² - 4ac > 0 then roots are real and distinct
• If b² - 4ac = 0 then roots are real and equal
• If b² - 4ac < 0 then the roots are not real
Here
b² - 4ac = 5² - (4 × 7 × 1) = 25 - 28 = - 3
Thus the 2 roots are not real
Answer:
a) 3.47% probability that there will be exactly 15 arrivals.
b) 58.31% probability that there are no more than 10 arrivals.
Step-by-step explanation:
In a Poisson distribution, the probability that X represents the number of successes of a random variable is given by the following formula:

In which
x is the number of sucesses
e = 2.71828 is the Euler number
is the mean in the given time interval.
If the mean number of arrivals is 10
This means that 
(a) that there will be exactly 15 arrivals?
This is P(X = 15). So


3.47% probability that there will be exactly 15 arrivals.
(b) no more than 10 arrivals?
This is 














58.31% probability that there are no more than 10 arrivals.
Answer is 7.
55+5X=90
5X=90-55
5X=35
X=35/5
X=7
The given equation is:
ax2 + bx + c = 0
We have the resolvent is:
x = (- b +/- root (b2 - 4ac)) / (2a)
The discriminant is:
b2 - 4ac = 0
The solution will be:
x = (- b) / (2a)
Thus, the equation has a real solution.
Answer:
option B