Given:
Eighteen 2.5 gallon buckets are needed to fill a cistern with water.
To find:
The constant of variation.
Solution:
If y is directly proportional to x, then


Where, k is constant of variation.
In the given problem, water in cistern (w) is directly proportional to number of buckets (n).

(Capacity of each bucket is 2.5 gallons)
Therefore, the constant of variation is 2.5.
Answer:
a.


b.


c.
Attached file
d.
Apparently the practice of smoking reduces the ability to fall asleep, demanding much more time in individuals who smoke, than in those who do not smoke.
Step-by-step explanation:
a, b) For the group of smoking individuals, the average time it takes to fall asleep and the standard deviation of those times is:


a, b) For the group of non-smoking individuals, the average time it takes to fall asleep and the standard deviation of those times is:


c. In the attached file you can see the diagram of points for the times, in the smoking and non-smoking groups.
d. Apparently the practice of smoking reduces the ability to fall asleep, demanding much more time in individuals who smoke, than in those who do not smoke.
Answer:
should be - 8
Step-by-step explanation:
-2*-2=4 4*-2=-8
Answer:
The answer to your question is 8 h
Step-by-step explanation:
Data
length of the ladder = 200 cm
distance between each rung = 20 cm
rate = 10 cm/h
fifth rung = ?
Process
1.- Calculate the total distance the tide must rise
distance = 20 cm x 4
= 80 cm because the first rung touches the water
2.- Calculate the time
rate = distance / time
-Solve for time
time = distance / rate
-Substitution
time = 80 cm / 10cm/h
-result
time = 8 h
Answer:
Step-by-step explanation:
The equation that models the height of the ball in feet as a function of time is

Where
is the initial height,
is the initial velocity and t is the time in seconds.
We know that the initial height is:
The initial speed is:

So the equation is:

The ball hits the ground when when
So

We use the quadratic formula to solve the equation for t
For a quadratic equation of the form

The quadratic formula is:

In this case

Therefore

We take the positive solution.
Finally the ball takes 2.47 seconds to touch the ground