Answer:
Option D) $275
Step-by-step explanation:
We are given the following information in the question:
Mean, μ = $235
Standard Deviation, σ = $20
We are given that the distribution of amount of money spent by students is a bell shaped distribution that is a normal distribution.
Formula:

We have to find the value of x such that the probability is 0.975
Calculation the value from standard normal z table, we have,

Approximately 97.5% of the students spent below $275 on textbook.
Answer:
b=2/3
Step-by-step explanation:
The table is given as:

The exponential function is given in the form

where a is the initial value and b is the multiplicative rate of change
When x=1, y=9, we have:

When x=3, y=4, we have:

Dividing the two equations:

The multiplicative rate of change, b is 2/3.
Solve the equation for x by find the A , B , C of the quadratic then applying the quadratic formula
3(2)(-1)=
3×2×-1=
3×2=6×-1=-6
-6 is the answer
Hi there!
When two lines intersect, we know that the ones on the opposite sides are equal to one another. Thus, we know that the angle opposite of the one marked with 90 degrees (on the other side of the intersection) is also 90 degrees.
We know that a full turn is 360 degrees. We can see that the two 90 degrees make up part of the turn, and the other pair of angles, both of which are equal to x (as per the reasoning above), make up the rest. We know that the two 90 degrees, added together, is equal to 180 degrees. This means, after subtracting 180 from 360, that 180 degrees are remaining that aren't the 2 90 degrees, and are make up of two angles both measuring x degrees.
As we know that they both measure x, then we know that we say 2x = 180, which gives us x = 90.
Hope this helps!