All categories

3 years ago

15 acres decreased by 80%

1 answer:

4 0

First, you have to find what 80% of 15 is. In order to do that you have to change 80% percent to decimal, which would be .80. Then, multiply .80 and 15 to get 12. Subtract 12 from 15 and your answer is 3.

You might be interested in

An unknown number y is 20 more than an unknown number x. The number y is also x less than 2. The equations to find x and y are s

zloy xaker [14]

Answer:

b)Add the equations to eliminate x.

Step-by-step explanation:

y= x+20

y= - x+2

Result of the addition: (-x cancels x)

2y = 22

y =11

11=x +20 -9 = x

11=9+2

11 = -9 +20

8 0

3 years ago

Please help me with this math problem, urgent please

cestrela7 [59]

Answer:

y = -3.5x + 15

Step-by-step explanation:

Your slope-intercept equation is always y = mx + b

Using this formula, we need to find slope first: m = (y2-y1) / (x2-x1)

Step 1: Find slope

m = (1-8) / (4-2)

m = -7/2

Step 2: Plug in into slope-intercept form

y = -3.5x + b

Step 3: Find <em>b </em>(Plug in a coordinate given)

1 = -3.5(4) + b

1 = -14 + b

b = 15

Step 4: Combine it all together

y = -3.5x + 15

And you have your final answer.

3 0

3 years ago

The following data comparing wait times at two rides at Disney are listed below: Position Pirates Splash Mountain Sample Size 32

myrzilka [38]

Answer:

a) $(14.68 -18.77) - 2.39 \sqrt{\frac{11.87^2}{32}+\frac{16.79^2}{30}} =-12.968$

$(14.68 -18.77) + 2.39 \sqrt{\frac{11.87^2}{32}+\frac{16.79^2}{30}} =4.788$

b) $t=\frac{14.68-18.77}{\sqrt{\frac{11.87^2}{32}+\frac{16.79^2}{30}}}}=-1.10$

Step-by-step explanation:

Data given and notation

$\bar X_{A}=14.68$ represent the mean for Pirates

$\bar X_{B}=18.77$ represent the mean for Splash Mountain

$s_{A}=11.87$ represent the sample standard deviation for the sample Pirates

$s_{B}=16.79$ represent the sample standard deviation for the sample Slpash Mountain

$n_{A}=32$ sample size selected for Pirates

$n_{B}=30$ sample size selected for Splash Mountain

$\alpha=0.02$ 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)

Part a

The confidence interval would be given by:

$(\bar X_A -\bar X_B) \pm t_{\alpha/2} \sqrt{\frac{s^2_{A}}{n_{A}}+\frac{s^2_{B}}{n_{B}}}$

The degrees of freedom are given by:

$df = n_A +n_B -2 = 32+30-2 = 60$

Since we want 98% of confidence the significance level is $\alpha =1-0.98 =0.02$ and $\alpha/2 =0.01$ , we can find in the t distribution with df =60 a critical value that accumulates 0.01 of the area on each tail and we got:

$t_{\alpha/2}= 2.39$

And replacing we got for the confidence interval:

$(14.68 -18.77) - 2.39 \sqrt{\frac{11.87^2}{32}+\frac{16.79^2}{30}} =-12.968$

$(14.68 -18.77) + 2.39 \sqrt{\frac{11.87^2}{32}+\frac{16.79^2}{30}} =4.788$

Part b

State the null and alternative hypotheses.

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

Null hypothesis: $\mu_{A} = \mu_{B}$

Alternative hypothesis: $\mu_{A} \neq \mu_{B}$

the statistic is given by:

$t=\frac{\bar X_{A}-\bar X_{B}}{\sqrt{\frac{s^2_{A}}{n_{A}}+\frac{s^2_{B}}{n_{B}}}}$ (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 info given like this:

$t=\frac{14.68-18.77}{\sqrt{\frac{11.87^2}{32}+\frac{16.79^2}{30}}}}=-1.10$

6 0

3 years ago

How many terms are in the following sequence? 131072, ..., 8, 4, 2

Klio2033 [76]

Answer:

17 terms

Step-by-step explanation:

131072 = 2^17

8 = 2^3

4 = 2^2

2 = 2^1

Apparently, the sequence is powers of 2 from 17 down to 1, so there are 17 terms in the sequence.

8 0

3 years ago

Identify the parent function that can be used to graph the function f(x)=-6[1/2x+3]+2/3

Sedaia [141]

Answer:

Step-by-step explanation:

8 0

3 years ago