Supplementary angles formula?

A wheel has a radius of 15 cm. Approximately how far does it travel in 4 revolutions?

ArbitrLikvidat [17]

Radius is 15 cm
Circumference = 2 pi r
C = 2 x 3.14 x 15cm
C = 94.2 cm
94.2 cm x 4 (revolutions) = 376.8 = D

7 0

3 years ago

6th out of 10 questions

Vlad [161]

The answer is D

To solve the answer you would have needed to multiply the reciprocal of $\frac{2}{7}$ but in this case, Unvi multiplied with the reciprocal of 14.

8 0

3 years ago

Evaulate the function at the indicated values h(t)=t+(3/t)i find h(x-1)

alex41 [277]

h(t)=t34−3t14

Note that the domain of h is [0,∞].

By differentiating,

h'(t)=34t−14−34t−34

by factoring out 34,

=34(1t14−1t34)

by finding the common denominator,

=34t12−1t34=0

⇒t12=1⇒t=1

Since h'(0) is undefined, t=0 is also a critical number.

Hence, the critical numbers are t=0,1.

I hope that this was helpful.

6 0

3 years ago

A study of the number of business lunches that executives in the insurance and banking industries claim as deductible expenses p

gizmo_the_mogwai [7]

Answer:

$t=\frac{9.1-8}{\sqrt{\frac{(1.9)^2}{40}+\frac{(2.1)^2}{50}}}}=2.604$

$p_v =2*P(t_{(88)}>2.604)=0.0108$

So the p value is a very low value and using any significance level for given $\alpha=0.05$ always $p_v$ so we can conclude that we have enough evidence to reject the null hypothesis, and there is enough evidence to conclude that the two means are significantly different at 5%

Step-by-step explanation:

Data given and notation

$\bar X_{1}=9.1$ represent the mean for the sample 1

$\bar X_{2}=8$ represent the mean for the sample 2

$s_{1}=1.9$ represent the sample standard deviation for the sample 1

$s_{2}=2.1$ represent the sample standard deviation for the sample 2

$n_{1}=40$ sample size for the group 1

$n_{2}=50$ sample size for the group 2

t would represent the statistic (variable of interest)

Concepts and formulas to use

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

Null hypothesis: $\mu_{1} = \mu_{2}$

Alternative hypothesis: $\mu_{1} \neq \mu_{2}$

If we analyze the size for the samples both are higher than 30 and the population deviations are not given, so for this case is better apply a t test to compare means, and the statistic is given by:

$t=\frac{\bar X_{1}-\bar X_{2}}{\sqrt{\frac{s^2_{1}}{n_{1}}+\frac{s^2_{2}}{n_{2}}}}$ (1)

t-test: Is used to compare group means. Is one of the most common tests and is used to determine whether the means of two groups are equal to each other.

Calculate the statistic

We can replace in formula (1) the results obtained like this:

$t=\frac{9.1-8}{\sqrt{\frac{(1.9)^2}{40}+\frac{(2.1)^2}{50}}}}=2.604$

Statistical decision

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

$df=n_{1}+n_{2}-2=40+50-2=88$

Since is a bilateral test the p value would be:

$p_v =2*P(t_{(88)}>2.604)=0.0108$

So the p value is a very low value and using any significance level for given $\alpha=0.05$ always $p_v$ so we can conclude that we have enough evidence to reject the null hypothesis, and there is enough evidence to conclude that the two means are significantly different at 5%

3 0

2 years ago

If twice a number is subtracted from 11, the result is 4 more than the number. What is the number?

Flauer [41]

Let the number = x.

So 2 times x subtracted from 11 is written as 11-2x

The result is 4 more than the number is written as 4 +x

Now you have 11-2x = 4 + x

We can now solve for x.

Add 2x to each side:

11 = 4 + 3x

Subtract 4 from each side:

7 = 3x

Divide both sides by 3:

x = 7/3

4 0

3 years ago