Answer:
9/35
Step-by-step explanation:
There are a total of 15 bulbs to choose from randomly. First a new bulb is chosen. Chance is 9/15 because 9 out of 15 are new.
Then there are only 14 bulbs left. Then a used bulb is chosen. Chance is 6/14 since 6 out of remaining 14 are used.
Total chance for this to happen is 9/15 * 6/14 = 54/210 = 9/35.
Pay=pay per hour times hours
A. M=12x
B. for more than 30, so
T=amoutn earned already (30hr normal)+overtime
T=12(30)+16y
T=360+16y
C.
hmm, 360 is if worked 30 hours, the rest is overtime
so
408=360+16y where y is overtime
minus 360 both sides
48=16y
divide both sides y 16
3=y
3 hours of overtime
<h3>
Answer: Choice B is correct</h3>
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Explanation:
Use a graphing tool like GeoGebra, Desmos, or your graphing calculator to plot each expression given as a separate y equation. Four parabolas should result.
The x intercept is the same as the root or zero of a function.
You should find that only choice B has a root thats larger than 4. That specific root being x = 7.
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A non-graphing approach:
You can use the quadratic formula or the factoring method to find the roots.
For choice A, it factors to (x+5)(x+6) = 0. The roots are x = -5 and x = -6 which aren't greater than 4. So we cross choice A off the list. Choices C and D are similar stories.
On the other hand, choice B factors to (x-7)(x+2) = 0 and it has roots of x = 7 and x = -2. This is another way to see why choice B is the answer.
Here are the steps for the quadratic formula for choice B

The quadratic formula is handy in case factoring is either not possible, or guess-and-check is too lengthy of a process. As you can probably tell, we could use the quadratic formula's results to help construct the factored form.
Answer:
Brad average typing rate in words per minute is 21
1260 divided by 60 = 21
(In case you meant 30 minutes)
1260 divided by 30 = 42
Step-by-step explanation:
In a typing class, the average number N of words per minute typed after t weeks of lessons is
N=157/(1+5.4e^-0.12t)
N=157/(1+5.4e
−
0.12t)
. Find the time necessary to type 75 words per minute
5 * 4 = 20
Answer: 20 quarter hours