What is the height of the pole? top O 12 ft O 125 ft O 18 ft O 182 ft

Emily ran her first lap in 75 seconds she ran her second lap in 69 seconds using percentages how much better was her second lap

julsineya [31]

Answer:

Her second lap was 8% better when compared to her first lap.

Step-by-step explanation:

Given:

Emily ran her first lap in 75 seconds she ran her second lap in 69 seconds.

Now, to find how much better was her second lap when compared to her first lap.

Emily ran her first lap in 75 seconds.

Emily ran her second lap in 69 seconds.

So, we get the difference in seconds:

$75-69=6\ seconds.$

Thus, in her second lap she was 6 seconds better than first.

Now, to get the percentage of her first lap better than second:

$\frac{6}{75}\times 100$

$=0.08\times 100$

$=8\%.$

Therefore, her second lap was 8% better when compared to her first lap.

7 0

3 years ago

Can you help me i don’t know the answers

Advocard [28]

1)

An irrational number is a number that a) can't be written as a fraction of two whole numbers AND b) is an infinite decimal without any sort of pattern.

For the first answer choice, clearly $\frac{1}{3}$ does not pass the first criterion so we look at the second choice.

Let's come back to $\sqrt{2}$ and $\pi$ .

$\frac{2}{9}$ doesn't meet our first criterion, and let's skip $\sqrt{3}$ for now.

It is often easier to disprove an irrational number than to prove one. There are a few famous irrationals to know (although there is an infinite number of irrationals). The most common are $\sqrt{2}, \pi, e, \sqrt{3}$ . For now, it's just helpful to know these and recognize them.

So we can check off $\sqrt{2}, \pi$ and $\sqrt{3}$ .

2)

For this next question, we know that $\sqrt{64} = 8$ . Clearly this isn't irrational. Likewise, $\frac{1}{2}$ isn't irrational. $\frac{16}{4} = \frac{4}{4} = 1$ , which is rational, leaving only $\frac{ \sqrt{20}}{5} = \frac{2 \sqrt{5} }{5}$ . By process of elimination, this is the correct answer. Indeed, $\sqrt{5}$ is an irrational number.

3) This notation means that we have 0.3636363636... and so on, to an infinite number of digits. It is called a repeating decimal.

But it can be written as a fraction because its pattern repeats, unlike for an irrational number.

Let's say $x=0.36363636...$ . Would you agree that $100x=36.36363636...$ ? (We choose to multiply by 100 because there are two decimals that repeat. For 1, choose 10, for 3 choose 1,000, and so on.)

Now, let's subtract x from 100x and solve.

$100x=36.36363636\\-x \ \ \ \ \ \ \ -0.36363636\\99x=36\\\\x= \dfrac{36}{99}= \dfrac{4}{11}$

Voila!

4 0

3 years ago

Read 2 more answers

Me podrían ayudar con esto?

xxTIMURxx [149]

Answer:

0

Step-by-step explanation:

This would be basically be zero/0 because anything times 0 is just nothing.

7 0

2 years ago

The population of a city increase exponentially at a rate of x% every 5 years

Lerok [7]

Answer:

1.1460277. Put in your decimal place given to you.

This is the percentage rate.

Step-by-step explanation:

f(x)=0=60100

55=120150

60100=a*b^0

120150/60100=60100/60100*b^5

b^5^(1/5)=5square root(120150/60100)=1.14860277

5 0

3 years ago

An object is heated to 100°. It is left to cool in a room that

stepladder [879]

Answer:

Step-by-step explanation:

Use Newton's Law of Cooling for this one. It involves natural logs and being able to solve equations that require natural logs. The formula is as follows:

$T(t)=T_{1}+(T_{0}-T_{1})e^{kt}$ where

T(t) is the temp at time t

T₁ is the enviornmental temp

T₀ is the initial temp

k is the cooling constant which is different for everything, and

t is the time (here, it's in minutes)

If we are looking first for the temp after 20 minutes, we have to solve for the k value. That's what we will do first, given the info that we have:

T(t) = 80

T₁ = 30

T₀ = 100

t = 5

k = ?

Filling in to solve for k:

$80=30+(100-30)e^{5k}$ which simplifies to

$50=70e^{5k}$ Divide both sides by 70 to get

$\frac{50}{70}=e^{5k}$ and take the natural log of both sides:

$ln(\frac{5}{7})=ln(e^{5k})$

Since you're learning logs, I'm assuming that you know that a natural log and Euler's number, e, "undo" each other (just like taking the square root of something squared). That gives us:

$-.3364722366=5k$