Are these fractions equivalent or nonequivalent?<br> 2/9 4/18

The volumes of two similar figures are 27 mm^3 and 1331 mm^3. If the surface area of the smaller figure is 18 mm^2, what is the

trasher [3.6K]

Volumes are in ratio 27 : 1331
so ratio od individual lengths = cube roots = 3 : 11
and surface areas will be in the ratio 3^2 : 11^2 = 9:121

so surface area of the larger figure is 121 * 18 / 9 = 242 mm^2

7 0

3 years ago

A moto maintained a constant speed of 13 miles per hour relative to the water in going 25 miles upstream and then returning. The

MrRa [10]

Answer:

current speed = 12 mph

Step-by-step explanation:

distance / rate = time

time upstream + time downstream = 26

25 / (13-c) + 25 / (13+c) = 26 ( c = current speed)

solve for c = 12 mi/hr

8 0

1 year ago

Question 2<br> Solve the equation.<br> a +3.7 = 4.1

beks73 [17]

Answer:

.4=a

Step-by-step explanation:

self explanatory

3 0

3 years ago

Read 2 more answers

For the hypothesis test H0: μ = 10 against H1: μ >10 and variance known, calculate the Pvalue for each of the following test

Basile [38]

Answer:

a) $p_v =P(Z>2.05)=1-P(z$

b) $p_v =P(Z>-1.84)=1-P(z$

c) $p_v =P(Z>0.4)=1-P(z$

Step-by-step explanation:

Some previous concepts

The p-value is the probability of obtaining the observed results of a test, assuming that the null hypothesis is correct.

A z-test for one mean "is a hypothesis test that attempts to make a claim about the population mean(μ)".

The null hypothesis attempts "to show that no variation exists between variables or that a single variable is no different than its mean"

The alternative hypothesis "is the hypothesis used in hypothesis testing that is contrary to the null hypothesis"

Hypothesis

Null hypothesis: $\mu=10$

Alternative hypothesis: $\mu >10$

If the random variable is distributed like this: $X \sim N(\mu,\sigma)$

We assume that the variance is known so the correct test to apply here is the z test to compare means, the statistic is given by the following formula:

$z_o=\frac{\bar X -\mu}{\sigma}$

Since we have the values for the statistic already calculated we can calculate the p value using the following formulas:

Part a

$p_v =P(Z>2.05)=1-P(z$

And in order to find the answer using excel we can use the following code:

"=1-NORM.DIST(2.05,0,1,TRUE)"

Part b

$p_v =P(Z>-1.84)=1-P(z$

And in order to find the answer using excel we can use the following code:

"=1-NORM.DIST(-1.84,0,1,TRUE)"

Part c

$p_v =P(Z>0.4)=1-P(z$

And in order to find the answer using excel we can use the following code:

"=1-NORM.DIST(0.4,0,1,TRUE)"

Conclusions

If we use a reference value for the significance, let's say $\alpha=0.05$ . For part a the $p_v$ so then we can reject the null hypothesis at this significance level.