Answer:
0.9007 is the probability that a student scored below 86 on this exam.
Step-by-step explanation:
We are given the following information in the question:
Mean, μ = 77
Standard Deviation, σ = 7
We are given that the distribution of examination grades is a bell shaped distribution that is a normal distribution.
Formula:

a) P(student scored below 86)
P(x < 86)
Calculation the value from standard normal z table, we have,

0.9007 is the probability that a student scored below 86 on this exam.
Answer:
<u>x = 36</u>
Step-by-step explanation:
180 - 126 = 54
90 + 54 + x = 180
144 + x = 180
180 - 144 = x
x = 36
Have a nice day!
Answer:
or
Step-by-step explanation:
The given quadratic equation is

Group the constant terms on the right hand side.


Divide through by 5.

Add the square of half the coefficient of x., which is
to both sides of the equation.

The left hand side is now a perfect square.

Take the square root of both sides;



or 
or 
or 
Answer:
C. 2d+3=12
Step-by-step explanation: