All categories

3 years ago

EASY MATH PROBLEMS! #8 and #10

Mathematics

1 answer:

xxMikexx [17]3 years ago

4 0

8. volume of cylinder is pi*r^2*h
So V= pi * (radius)^2 * height =720* pi

we know circumference = 2 * pi * r

if we look at first equation. We can edit it like
pi * r * r * h

now we can say it kind of looks like circumference equation but missing 2 so we multiply both sides by 2
2 * pi * r * r * h = 2 * 720 * pi

We can take out the 2 * pi * r and put in circumference (C)

c * r * h = 1440 * pi

We we know h is 20 so

c * r * 20 = 1440 * pi
c * r = 72 * pi

we have to solve for r first so break circumference back up

2 * pi * r * r = 72 * pi

r * r = 36
r = 6

plug into circum equation
C = 2 * pi * 6
C = 12 * pi

10. I assume the cylinders fill uo the box and if radius is 1.5 then diameter is 3. There are 5 in a row some 3 * 5 = 15 box length.
2 in a column so 2 * 3 = 6 box width
the height is 5

So
l * h * w = V

6 * 5 * 15 =V

V = 450

You might be interested in

Twice the difference between a number

Alecsey [184]

Answer:

Let x = the number

2(x-5) = 9

2x - 10 = 9

2x = 19

x = 9.5

Step-by-step explanation:

7 0

2 years ago

The standard unit for length is the ____. yard meter foot milliter please help its due in 6 mins!!!

LenaWriter [7]

Answer:

Meter

Step-by-step explanation:

The standard unit of length based on the metric system is a meter (m). According to the length that needs to be measured, we can convert a meter into various units like millimeters (mm), centimeter (cm), and kilometer (km).

7 0

3 years ago

A study was made of seat belt use among children who were involved in car crashes that caused them to be hospitalized. It was fo

borishaifa [10]

Answer:

a) $P(5$

And we can find this probability with this difference:

$P(-1.90$

And using the norma standard distribution or excel we got:

$P(-1.90$

b) $P(X>6) =P(Z> \frac{6-7.37}{1.25}) = P(Z>-1.096)$

And using the complement rule we got:

$P(Z>-1.096) =1-P(Z$

Step-by-step explanation:

Previous concepts

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".

Part a

Let X the random variable that represent the variable of interest of a population, and for this case we know the distribution for X is given by:

$X \sim N(7.37,1.25)$

Where $\mu=7.37$ and $\sigma=1.25$

We are interested on this probability

$P(5$

And the best way to solve this problem is using the normal standard distribution and the z score given by:

$z=\frac{x-\mu}{\sigma}$

If we apply this formula to our probability we got this:

$P(5$

And we can find this probability with this difference:

$P(-1.90$

And using the norma standard distribution or excel we got:

$P(-1.90$

Part b

For this case we want this probability:

$P(X>6)$

And we can use the z score and we got:

$P(X>6) =P(Z> \frac{6-7.37}{1.25}) = P(Z>-1.096)$

And using the complement rule we got:

$P(Z>-1.096) =1-P(Z$

8 0

3 years ago

If a sponsored link was delivered 100 times and 10 people clicked on it, then the number of impressions is 100, the number of cl

Rudik [331]

Answer:

Option A.

Step-by-step explanation:

It is given that a sponsored link was delivered 100 times and 10 people clicked on it.

Number of impressions = 100

Number of clicks = 10

The formula for click-through-rate (CTR) is

$CTC=\dfrac{\text{Total measured clicks}}{\text{Total measured impression}}\times 100$

$CTC=\dfrac{10}{100}\times 100$

$CTC=10$

The click-through-rate (CTR) would be 10%. Therefore, the correct option is A.

7 0

3 years ago

-9.b = 45<br> b =<br> What is the answer I need to know the answe

BaLLatris [955]

Answer:

b=-5

Step-by-step explanation:

Divide by -9 to eliminate the -9 on -9b

(Since -9b is the same thing as -9 times b we can use the inverse of multiplication which is division to eliminate the -9 from b but we need to do it on both sides to make it balance)

-9b/-9=45/-9

b=-5

7 0

2 years ago