10 meters = how many feet?

What is the value of the rational expression below when x is equal to 4? 12+x/4+x

riadik2000 [5.3K]

12+4=16
4+4=8
16/8=2

C!

8 0

4 years ago

600 or 600 decreased by 20% and then increased by 20% of the result? Which amount is larger and by how much

ohaa [14]

Answer:

The initial value of 600 is larger and larger by 24.

Step-by-step explanation:

First of all a 20% decreased of 600.

So, the new value will be $600(1 - \frac{20}{100}) = 600 \times 0.8 = 480$ .

Now, then it is increased by 20% i.e. 480 will be increased by 20%.

So, the new value will be $480(1 + \frac{20}{100}) = 480 \times 1.2 = 576$ .

Therefore, the initial value of 600 is larger and larger by (600 - 576) = 24. (Answer)

3 0

3 years ago

Eighty percent of the tickets for the baseball game on july 4th been sold. there are 20,000 tickets. how many been sold

Viktor [21]

16000 tickets have been sold.

Glad I could help :)

6 0

3 years ago

A student has a 2% salt water solution and a 7% salt water solution. To best imitate salt water at a local beach, he needs 1 lit

FromTheMoon [43]

Let

x-------> the amount of $2\%$ solution

y--------> the amount of $7\%$ solution

we know that

$2\%=0.02\\7\%=0.07\\3.5\%=0.035$

so

$x+y=1$

$y=1-x$ -------> equation A

$0.02x+0.07y=0.035$ -------> equation B

substitute equation A in equation B

$0.02x+0.07(1-x)=0.035$

$0.02x+0.07-0.07x=0.035$

$0.05x=0.035$

$x=0.7\ liters$

find the value of y

$y=1-x$

$y=1-0.7=0.3\ liters$

therefore

The student need $0.7\ liters$ of $2\%$ solution and $0.3\ liters$ of $7\%$ solution

<u>the answer is</u>

A) The percent values were written incorrectly in the equation

B) The amount of 7% solution should be written as 1 – x, not x – 1.

8 0

3 years ago

Read 2 more answers

Fowle Marketing Research Inc., bases charges to a client on the assumption that telephone surveys can be completed in a mean tim

sergejj [24]

Answer:

a) Null hypothesis: $\mu \leq 15$

Alternative hypothesis: $\mu > 15$

b) $t=\frac{17-15}{\frac{4}{\sqrt{35}}}=2.958$

c) $p_v =P(t_{34}>2.958)=0.0028$

d) If we compare the p value and the significance level given $\alpha=0.01$ we see that $p_v$ so we can conclude that we have enough evidence to reject the null hypothesis, so we can conclude that the true mean is higher than 15 at 1% of signficance.

Step-by-step explanation:

Data given and notation

The sample mean is given by:

$\bar X = \frac{\sum_{i=1}^n X_i}{n}$

And the sample deviation is:

$s = \sqrt{\frac{\sum_{i=1}^n (X_i -\bar X)^2}{n-1}}$

$\bar X=17$ represent the sample mean

$s=4$ represent the sample standard deviation

$n=35$ sample size

$\mu_o =15$ represent the value that we want to test

$\alpha=0.01$ represent the significance level for the hypothesis test.

z would represent the statistic (variable of interest)

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

Part a State the null and alternative hypotheses.

We need to conduct a hypothesis in order to check if the mean is less or equal than 15, the system of hypothesis would be:

Null hypothesis: $\mu \leq 15$

Alternative hypothesis: $\mu > 15$

Since we don't know the population deviation, 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".

Part b Calculate the statistic

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

$t=\frac{17-15}{\frac{4}{\sqrt{35}}}=2.958$

Part c P-value

The degrees of freedom are given by:

$df = n-1= 35-1=34$

Since is a right tailed test the p value would be:

$p_v =P(t_{34}>2.958)=0.0028$

Part d Conclusion

If we compare the p value and the significance level given $\alpha=0.01$ we see that $p_v$ so we can conclude that we have enough evidence to reject the null hypothesis, so we can conclude that the true mean is higher than 15 at 1% of signficance.

7 0

3 years ago