Find the inverse of f(x)=(1/3)^x

115 = 20 + 2.5x Answers X= 38 X= - 37/38

KIM [24]

The answer would be X=38

7 0

3 years ago

Audrey's father gave her 20 tokens to use at Action

rjkz [21]

Answer:

5 tokens

Step-by-step explanation:

She spent 1 out of every 4 tokens, meaning there are a couple of sets of 4 that we don't know many they are yet that she kept taking from every set 1 token, so if we do,

(Her total tokens) 20 ÷ 4 = 5.
This means that there's 5 sets, then we take 1 from every set so 1 × 5 = 5, that's it

I don't know if that was quite clear tho you can imagine it in a more virtual than mathematical way if you like,

Now Imagine you have 20 tokens in your hand, and you divide them into 5 sets, each set is a set of 4, you keep 3 in your hand then put 1 on a table, then you do this 5 times you'll end up with 5 tokens on the table and 15 in your hand.

You can try that yourself if you want it to be more clear.

Take 20 small pieces of paper, sticky notes or coins whatever you like, then divide them into sets of 4, then lastly take only 1 from each set (and by the way you'll notice that dividing each set into a set of 4 will make you automatically end up with 5 sets) now count all the 1's you collected from each set
they should be 5.

8 0

2 years ago

Read 2 more answers

How can you place value and period names to read and write 12,324,904 in word form?

FrozenT [24]

It is written/spoken like so:

"Twelve million three hundred and twenty four thousand nine hundred and four"

6 0

3 years ago

Read 2 more answers

The population of a city is 451,400. The population is expected to decrease at a rate of 3.2% each year.

blondinia [14]

Answer:

Find out the what function equation represents the population of the city after t years .

To prove

The population of a city is 451,400. The population is expected to decrease at a rate of 3.2% each year.

This can be represented by exponential decreasing function.

$f(t) = a (1 - r)^{t}$

Where a is the initial value.

r is the rate in decimal form

t is the time.

Here

a = 451,400

3.2 % is written in the decimal form.

$= \frac{3.2}{100}$

= 0.032

Put in the formula

$f(t) = 451400 (1 - 0.032)^{t}$

$f(t) = 451400 (0.968)^{t}$

Therefore the decrease in the population of the city after t years is represented by

$f(t) = 451400 (0.968)^{t}$

5 0

3 years ago

Read 2 more answers

Suppose you read online that children first count to 10 successfully when they are 32 months old, on average. You perform a hypo

creativ13 [48]

Answer:

$p_v =2*P(t_{(35)}$

Step-by-step explanation:

Assuming this info from R

hist(gifted$count)

## Min. 1st Qu. Median Mean 3rd Qu. Max.

## 21.00 28.00 31.00 30.69 34.25 39.00

## Sd

## [1] 4.314887

Data given and notation

$\bar X=30.69$ represent the mean

$s=4.3149$ represent the sample standard deviation

$n=36$ sample size

$\mu_o =32$ represent the value that we want to test

$\alpha$ represent the significance level for the hypothesis test.

t would represent the statistic (variable of interest)

$p_v$ represent the p value for the test (variable of interest)

State the null and alternative hypotheses.

We need to conduct a hypothesis in order to check if the mean is different than 32, the system of hypothesis would be:

Null hypothesis: $\mu = 32$

Alternative hypothesis: $\mu \neq 32$

If we analyze the size for the sample is > 30 but we don't know the population deviation so is better apply a t test to compare the actual mean to the reference value, and the statistic is given by:

$t=\frac{\bar X-\mu_o}{\frac{s}{\sqrt{n}}}$ (1)

t-test: "Is used to compare group means. Is one of the most common tests and is used to determine if the mean is (higher, less or not equal) to an specified value".

Calculate the statistic

We can replace in formula (1) the info given like this:

$t=\frac{30.69-32}{\frac{4.3149}{\sqrt{36}}}=-1.822$

P-value

The first step is calculate the degrees of freedom, on this case:

$df=n-1=36-1=35$

Since is a two sided test the p value would be:

$p_v =2*P(t_{(35)}$

7 0

3 years ago