Answer:
The probability of finding a sample mean less than 18 hours is 0.0082
Step-by-step explanation:
To find the probability of finding a sample mean less than 18 hours, we need to calculate the z-score of this sample mean 18. And the probability of finding a sample mean less than 18 hours is P(z<z(18)).
Z-score can be calculated as follows:
z(18)=
where
- X is the sample mean (18 hours)
- M is the average hours dentists spend per week on fillings (20 hours)
- s is the standard deviation (10 hours)
- N is the sample size (144)
Putting the numbers, we get:
z(18)=
Using z- table we can find that P(z<z(18)) = 0.0082
Answer:
No, You can't. You have to make their denominators equal!

Step-by-step explanation:
So first, you make their denominators equal!

Multiplying both the numerator and denominator with the same number results in the same fraction, just un-simplified
So, we input it!

There you go!
Hope you get better at math!(gets wayyyyyyyyyyy...y more complicated later)
Hope this helps!
See Ya!
P.S. Stay Safe!
Volume of a rectangular prism = l × w × h.
In this case,
V = 270 cubic feet
l = 15 feet
w = 4 ft
h = ?
Plug our values into the volume formula.
270 cubic feet = 15 feet × 4 feet × h.
Simplify the right side
270 = 60 × h.
Divide each side by 60.
4.5 = h
The height is 4.5 feet.