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4 years ago

Rank the following in order from least precise to most precise. 915 meters, 21000 grams, 8.43 inches, and 5.426 seconds

Mathematics

2 answers:

Allushta [10]4 years ago

8 0

Answer : The order from least precise to most precise is,

21000 grams < 915 meters < 8.43 inches < 5.426 seconds

Step-by-step explanation :

Precision : It is defined as the closeness of two or more measurements to each other.

For Example: If you weigh a given substance five times and you get 1.8 kg each time. Then the measurement is said to be precise.

Level of precision is determined by the maximum number of decimal places.

or,

Level of exactness in a number's digits, such as number 54.6 having precision 1 (one decimal digit).

A number with end zeroes ("00") has a negative precision, such as 600 having precision -2, or 5,000 as precision -3.

A whole number (not ending in "0") has precision 0.

From the given measurements we conclude that, the order from least precise to most precise is:

21000 grams < 915 meters < 8.43 inches < 5.426 seconds

frez [133]4 years ago

7 0

Least precise to most precise: 21000 grams, 915 and 8.43 are the same precision, 5.426 seconds.

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3 years ago

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Step-by-step explanation:

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4 years ago

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Answer:

Check the explanation below.

Step-by-step explanation:

Hello!

The study variable is:

X: Arsenic level of well water (ppb)

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To study the population mean the variable needs to have at least a normal distribution. If the information of the sample was available we could make a normality test to check if it's distribution is normal or not. Since the Students t cannot be used unless the variable has a normal distribution, we cannot choose this statistic to make the hypothesis test, the same happens with the standard normal, if the condition of a variable with normal distribution is not met, the statistic cannot be used.

The most recommendable is to apply the Central Limit Theorem, this theorem states:

Be a population with probability function f(X;μ,δ²) from which a random sample of size n is selected. Then the distribution of the sample mean tends to the normal distribution with mean μ and variance δ²/n when the sample size tends to infinity.

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σ/√n

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$Z= \frac{7.3-8}{\frac{2.4}{\sqrt{36} } }$

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If it is equal or less than the level of significance, then you reject the null hypothesis.

d) The calculated p-value (0.04006) is less than α (0.05), the decision is to reject the null hypothesis.

e) At a level of 5%, the decision is to reject the null hypothesis. This means that there is significant evidence to think that the average level of arsenic in the well water is less than 8 ppb.

I hope it helps!

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