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2 years ago

5

A lion runs 45 mph and crosses a bridge in 40 seconds. A cheetah runs across the same bridge in 30 seconds. How fast does the ch

eetah run?

1 answer:

Aleks04 [339]2 years ago

7 0

Answer:

60 mph because the cheetah runs at 4/3 of the lion's pace, which is 45 mph. 4/3 x 45 is 60.

You might be interested in

According to a Pew Research survey, about 27% of American adults are pessimistic about the future of marriage and the family. Th

IgorLugansk [536]

Answer:

P(X≤5)=0.5357

Step-by-step explanation:

Using the binomial model, the probability that x adults from the sample, are pessimistic about the future is calculated as:

$P(x)=\frac{n!}{x!(n-x)!} *p^{x}*(1-p)^{n-x}$

Where n is the size of the sample and p is the probability that an adult is pessimistic about the future of marriage and family. So, replacing n by 20 and p by 0.27, we get:

$P(x)=\frac{20!}{x!(20-x)!}*0.27^{x}*(1-0.27)^{20-x}$

Now, 25% of 20 people is equal to 5 people, so the probability that, in a sample of 20 American adults, 25% or fewer of the people are pessimistic about the future of marriage and family is equal to calculated the probability that in the sample of 20 adults, 5 people of fewer are pessimistic about the future of marriage and family.

Then, that probability is calculated as:

P(X≤5)= P(1) + P(2) + P(3) + P(4) + P(5)

Where:

$P(0)=\frac{20!}{0!(20-0)!}*0.27^{0}*(1-0.27)^{20-0}=0.0018$

$P(1)=\frac{20!}{1!(20-1)!}*0.27^{1}*(1-0.27)^{20-1}=0.0137$

$P(2)=\frac{20!}{2!(20-2)!}*0.27^{2}*(1-0.27)^{20-2}=0.0480\\P(3)=\frac{20!}{3!(20-3)!}*0.27^{3}*(1-0.27)^{20-3}=0.1065\\P(4)=\frac{20!}{4!(20-4)!}*0.27^{4}*(1-0.27)^{20-4}=0.1675\\P(5)=\frac{20!}{5!(20-5)!}*0.27^{5}*(1-0.27)^{20-5}=0.1982$

Finally, P(X≤5) is equal to:

P(X≤5) = 0.0018+0.0137 + 0.0480 + 0.1065 + 0.1675 + 0.1982

P(X≤5) = 0.5357

3 0

2 years ago

John is participating in a marathon that is 26.2 miles. His distance (d, in miles) depends on his time (t, in hours). Which is a

madreJ [45]

The range of a function is representative of the values on the y-axis. In this case, the graph will contain distance on the y-axis at is the dependent variable, while the independent variable is time.

We know that the minimum value of the distance will be 0, given that there can be no negative distance. Moreover, the maximum value is 26.2 miles, since the marathon will then be over. Therefore, a good range for the situation will be 0-27 miles.

6 0

2 years ago

Is the average (arithmetic mean) of x and y greater than 20? the average (arithmetic mean) of 2x and 2y is 48. x = 3y?

AysviL [449]

2x + 2y = 48
2(x + y) = 48
x + y = 24
mean = 24/2 = 12

less than 20

4 0

2 years ago

Joan is hiking. She wants to cover 1,600 feet. She hikes 600 feet every 3 hours.

Stella [2.4K]

Joan's remaining distance is reduced by (600 ft)/(3 hours) = 200 ft/hour. She starts with 1600 ft remaining, so her distance remaining (y) after x hours is
.. y = -200x +1600

In order for the distance remaining to be zero, you must have
.. 0 = -200x +1600
.. 200x = 1600
.. x = 1600/200 = 8

It will take Joan 8 hours to hike 1600 ft.

6 0

2 years ago

In order to estimate the average electricity usage per month, a sample of 125 residential customers were selected, and the month

mr_godi [17]

Answer:

[895.05; 940.81]kWh

Step-by-step explanation:

Hello!

Be X: monthly electricity usage by a residential customer

X~N

σ²: 12100KWh²

To estimate the population mean using a 98% CI you have to use the following formula

[X[bar]± $Z_{1-\alpha /2}$ * $\frac{Sigma}{\sqrt{n} }$ ]

1-α: 0.98

α0.02

α/2: 0.01

1-α/2:0.99

$Z_{1-\alpha /2}= Z_{0.99}= 2.326$

n= 125

X[bar]= ∑X/n= 228565/125= 917.93

[917.93±2.326 * $\frac{110}{\sqrt{125} }$ ]

[895.05; 940.81]

Using a 98% confidence level you'd expect that the interval [895.05; 940.81]kWh will include the average monthly electricity usage of residential customers.

I hope this helps!

Raw data:

Electric Usage

765

1139

714

687

1027

1109

749

799

911

631

975

717

1232

806

637

894

856

896

1272

1224

621

606

898

723

817

746

933

595

851

1027

770

685

750

1198

975

678

1050

886

826

1176

583

841

1188

692

733

791

584

1163

593

1234

603

1044

1233

1178

598

904

778

693

590

845

893

1028

975

788

1240

1253

854

1185

1164

741

1058

1053

795

1198

1240

1140

959

938

1008

1035

1085

1100

680

1006

977

1042

1252

943

1165

1014

912

791

612

935

864

953

667

1005

1063

1095

1086

810

1032

970

1099

1229

892

1074

579

754

1007

1116

583

763

1231

966

962

1132

738

1033

697

891

840

725

1031

7 0

2 years ago