I PROMISE BRANLIEST TO THE FIRST ANSWER SUBMITTED!

Could you help me plz

Nadya [2.5K]

Answer:

Step-by-step explanation:

(For a circle)

Circumference formula: π*2r

Area formula: π*r^2

1:

A)

π*2(3) =>6π=>18.84 m

B)

π*(3)^2=>9π=>28.27 m^2

2.

A)

π*2(3.1)=>6.2π=>19.47 m

B)

π*(3.1)^2=>9.61π=>30.19 m^2

6 0

3 years ago

The owner of a motel has 2900 m of fencing and wants to enclose a rectangular plot of land that borders a straight highway. If s

navik [9.2K]

Answer:

Step-by-step explanation:

Given that the owner of a motel has 2900 m of fencing and wants to enclose a rectangular plot of land that borders a straight highway.

Fencing is used for 2times length and 1 width if highway side is taken as width

So we have 2l+w = 2900

Or w = 2900-2l

Area of the rectangular region = lw

$A(l) = l(2900-2l) = 2900l-2l^2\\$

Use derivative test to find the maximum

$A'(l) = 2900-4l\\A"(l) = -4$

So maximum when I derivative =0

i.e when $l =\frac{2900}{4} =725$

Largest area = A(725)

= $725(2900-2*725)\\= 1051250$

1051250 sqm is area maximum

3 0

3 years ago

Please answer and put how

muminat

6 + m/4 = 3 (subtract 6 from both sides)
m/4 = -3 (multiply both sides by 4)
m = -12

Can plug in to original equation to check work:
6 - 12/4 = 3
6 - 3 = 3
3 = 3

The answer m = -12 checks out

3 0

3 years ago

Read 2 more answers

HELP! Whoever gets it right gets brainliest!!

aleksandrvk [35]

Answer:

D infitently Many

Step-by-step explanation:

A system of linear equations usually has a single solution, but sometimes it can have no solution (parallel lines) or infinite solutions (same line). This article reviews all three cases. One solution. A system of linear equations has one solution when the graphs intersect at a point.

6 0

3 years ago

Daily-high temperature measurements for 40 consecutive days are recorded for a particular city. The mean daily-high temperature

Vesnalui [34]

Answer:

$t=\frac{21.5-22}{\frac{1.5}{\sqrt{40}}}=-2.108$

$p_v =P(t_{39}$

Conclusion

If we compare the p value and the significance level given $\alpha=0.01$ we see that $p_v>\alpha$ so we can conclude that we have enough evidence to FAIL to reject the null hypothesis, so we can conclude that the mean temperature actually its NOT significant less then 22 at 1% of signficance.

(D) P-val=0.021, fail to reject the null hypothesis

Step-by-step explanation:

1) Data given and notation

$\bar X=21.5$ represent the mean for the temperatures

$s=1.5$ represent the sample standard deviation

$n=40$ sample size

$\mu_o =22$ represent the value that we want to test

$\alpha=0.01$ 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 less than 22C, the system of hypothesis would be:

Null hypothesis: $\mu \geq 22$

Alternative hypothesis: $\mu < 22$

If we analyze the size for the sample is > 30 and 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:

$t=\frac{21.5-22}{\frac{1.5}{\sqrt{40}}}=-2.108$

P-value

We can calculate the degrees of freedom like this:

$df=n-1=40-1=39$

Since is a one left tailed test the p value would be:

$p_v =P(t_{39}$

Conclusion

If we compare the p value and the significance level given $\alpha=0.01$ we see that $p_v>\alpha$ so we can conclude that we have enough evidence to FAIL to reject the null hypothesis, so we can conclude that the mean temperature actually its NOT significant less then 22 at 1% of signficance.

The best option would be:

(D) P-val=0.021, fail to reject the null hypothesis

5 0

3 years ago