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3 years ago

How do you find percent change??

2 answers:

6 0

To calculate the percentage increase: First: work out the difference (increase) between the two numbers you are comparing. Then: divide the increase by the original number and multiply the answer by 100. If your answer is a negative number then this is a percentage decrease

Lady bird [3.3K]3 years ago

5 0

To find percent change find the difference between the two numbers. Then, set up a proportion.

difference is to smaller number as x is to 100.
Cross multiply and solve for x.

Hope this helps!

You might be interested in

Which ratio forms a proportion with 18/27

JulsSmile [24]

Answer:

$\frac{2}{3}$

Step-by-step explanation:

The given ratio is $\frac{18}{27}$

9 is the common factor of 18 and 27

divide numerator and denominator by 9

$\frac{18/9}{27/9} =\frac{2}{3}$

hence $\frac{2}{3}$ is proportion with $\frac{18}{27}$

6 0

2 years ago

In a game using a spinner with five equal parts numbered 1 to 5, a contestant wins when the spinner lands on an odd number. Is t

gayaneshka [121]

Answer:

A. yes

Step-by-step explanation:

The contestant has a 60% chance of winning because they could either spin 1, 3, or 5.

However, unless there's another player who can only spin evens, it's not fair, because the contestant who spins odds has a 60% chance, while this player will only have a 40% chance.

3 0

1 year ago

Solve using Fourier series.

Olin [163]

With $2L=\pi$ , the Fourier series expansion of $f(x)$ is

$\displaystyle f(x)\sim\frac{a_0}2+\sum_{n\ge1}a_n\cos\dfrac{n\pi x}L+\sum_{n\ge1}b_n\sin\dfrac{n\pi x}L$
$\displaystyle f(x)\sim\frac{a_0}2+\sum_{n\ge1}a_n\cos2nx+\sum_{n\ge1}b_n\sin2nx$

where the coefficients are obtained by computing

$\displaystyle a_0=\frac1L\int_0^{2L}f(x)\,\mathrm dx$
$\displaystyle a_0=\frac2\pi\int_0^\pi f(x)\,\mathrm dx$

$\displaystyle a_n=\frac1L\int_0^{2L}f(x)\cos\dfrac{n\pi x}L\,\mathrm dx$
$\displaystyle a_n=\frac2\pi\int_0^\pi f(x)\cos2nx\,\mathrm dx$

$\displaystyle b_n=\frac1L\int_0^{2L}f(x)\sin\dfrac{n\pi x}L\,\mathrm dx$
$\displaystyle b_n=\frac2\pi\int_0^\pi f(x)\sin2nx\,\mathrm dx$

You should end up with

$a_0=0$
$a_n=0$
(both due to the fact that $f(x)$ is odd)
$b_n=\dfrac1{3n}\left(2-\cos\dfrac{2n\pi}3-\cos\dfrac{4n\pi}3\right)$

Now the problem is that this expansion does not match the given one. As a matter of fact, since $f(x)$ is odd, there is no cosine series. So I'm starting to think this question is missing some initial details.

One possibility is that you're actually supposed to use the even extension of $f(x)$ , which is to say we're actually considering the function

$\varphi(x)=\begin{cases}\frac\pi3&\text{for }|x|\le\frac\pi3\\0&\text{for }\frac\pi3$

and enforcing a period of $2L=2\pi$ . Now, you should find that

$\varphi(x)\sim\dfrac2{\sqrt3}\left(\cos x-\dfrac{\cos5x}5+\dfrac{\cos7x}7-\dfrac{\cos11x}{11}+\cdots\right)$

The value of the sum can then be verified by choosing $x=0$ , which gives

$\varphi(0)=\dfrac\pi3=\dfrac2{\sqrt3}\left(1-\dfrac15+\dfrac17-\dfrac1{11}+\cdots\right)$
$\implies\dfrac\pi{2\sqrt3}=1-\dfrac15+\dfrac17-\dfrac1{11}+\cdots$

as required.

5 0

2 years ago

Equivalent expression for 7a+21

Mila [183]

Answer:

Step-by-step explanation:

If you factor the expression 7a+21 you can get:

7 × (a+3)

6 0

3 years ago

Write an expression that represents the value in cents of n nickels

erma4kov [3.2K]

An expression does not have an equal sign.
Since the value of a nickel is 5 cents and you want to find out the value of n nickels (which means if you had any number of nickels) the expression would be
.05n

8 0

2 years ago

Read 2 more answers