Write down the equation for the stoichiometric combustion of propane (C3H8).

An escalator in a shopping center is designed to move 50 people, 75 kg each, at a constant speed of 0.6 m/s at 450 slope. Determ

REY [17]

Answer:

Power required to drive the escalator shall be equal to the rate at which the energies of the persons is increased.

$Energy=n\times mass\times g\times h\\\\\therefore Power=n\times mass\times g\times \frac{dh}{dt}\\\\Power=50\times 75\times 9.81\times 0.6sin(45)\\\\Power=15.607kW$

As we infer from the above equation If the velocity of the escalator is doubled then the Power required will also be doubled and become 31.215kW

3 0

4 years ago

Suppose a consumer advocacy group would like to conduct a survey to find the proportion p of consumers who bought the newest gen

Anvisha [2.4K]

Answer:

a) Sample size = 1691

b) 95% Confidence Interval = (0.3696, 0.4304)

Explanation:

(a) How large a sample n should they take to estimate p with 2% margin of error and 90% confidence?

The margin of error is given by

$MoE = z \cdot \frac{\sqrt{p(1-p)} }{\sqrt{n} } \\\\$

Where z is the corresponding z-score for 90% confidence level

z = 1.645 (from z-table)

for p = 0.50 and 2% margin of error, the required sample size would be

$n = \frac{1.645^{2} \cdot 0.50(1-0.50)}{0.02^{2}} \\\\n = \frac{0.6765}{0.0004} \\\\n = 1691\\$

(b) The advocacy group took a random sample of 1000 consumers who recently purchased this mobile phone and found that 400 were happy with their purchase. Find a 95% confidence interval for p.

The sample proportion is

p = 400/1000

p = 0.40

z = 1.96 (from z-table)

n = 1000

The confidence interval is given by

$CI = p \pm z \cdot \sqrt{\frac{p(1-p)}{n} } \\\\CI = 0.40 \pm 1.96 \cdot \sqrt{\frac{0.40(1-0.40)}{1000} } \\\\CI = 0.40 \pm 1.96 \cdot 0.01549 \\\\CI = 0.40 \pm 0.0304 \\\\CI = 0.40 - 0.0304 \: and \: 0.40 + 0.0304\\\\CI = (0.3696 ,\: 0.4304)$

Therefore, we are 95% confident that the proportion of consumers who bought the newest generation of mobile phone were happy with their purchase is within the range of (0.3696, 0.4304)

What is Confidence Interval?

The confidence interval represents an interval that we can guarantee that the target variable will be within this interval for a given confidence level.

3 0

3 years ago

While you are driving you see an animal standing or walking on the side of the road. You should..

STatiana [176]

Take caution, and slow down, it could run out in the middle of the road. Try going around it if possible.

8 0

3 years ago

Write in an Excel cell the appropriate @RISK function for a binomial distribution that results from 50 trials with probability o

borishaifa [10]

Answer:

Binomial Function

I got my output using the formula = 1 - BINOMDIST (17, 50, 0.3, TRUE)

Then got the cumulative probability distribution at 17 to be 0.2178

Explanation:

To draw a normal distribution:

1. Got to '@risk' and click on 'defined distribution'

2. Select 'binomial' in function block

3. enter formula in cell formula and click okay

The use of @RISK to draw a binomial distribution of 50 trials and probability of success as 0.3 by entering formular =RISKBINOMIAL (50, 0.3).

6 0

3 years ago

The ________ is considered the normal operating control of an air conditioner, according to the Standards of Practice. thermosta

mamaluj [8]

Answer:

Thermostat

Explanation:

The thermostat is considered the normal operating control of an air conditioner, according to the Standards of Practice.

8 0

2 years ago