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3 years ago

The difference of a number n and the number 8 is 42. Which of

Mathematics

1 answer:

MissTica3 years ago

5 0

Answer:

B) n-8=42

Step-by-step explanation:

"difference" means subtraction.

the number is represented by "n" in this problem.

"and" indicates where the symbol goes.

"is" means "=".

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Write 125 as a product of primes. Use index notation when giving your answer.

Mnenie [13.5K]

Answer:

5^3

Step-by-step explanation:

125= 5*25

25=5*5

5 is a prime number and there are 3 of them so the answer in index notation will be 5^3

3 0

2 years ago

Standard form of -2x^2+8x+5

Ksivusya [100]

-2x^2+8x+5 is the standard form

5 0

3 years ago

Persons having Raynaud's syndrome are apt to suffer a sudden impairment of blood circulation in fingers and toes. In an experime

Citrus2011 [14]

Answer:

There is enough evidence to say that the true average heat output of persons with the syndrmoe differs from the true average heat output of non-sufferers.

Step-by-step explanation:

We have to perform a hypothesis test on the difference between means.

The null and alternative hypothesis are:

$H_0: \mu_1-\mu_2=0\\\\H_a: \mu_1-\mu_2$

μ1: mean heat output for subjects with the syndrome.

μ2: mean heat output for non-sufferers.

We will use a significance level of 0.05.

The difference between sample means is:

$M_d=\bar x_1-\bar x_2=0.63-2.09=-1.46$

The standard error is

$s_{M_d}=\sqrt{\sigma_1^2/n_1+\sigma_2^2/n_2}=\sqrt{0.3^2/9+0.5^2/9}=\sqrt{ 0.038 } \\\\ s_{M_d}=0.194$

The t-statistic is

$t=\dfrac{M_d}{s_{M_d}}=\dfrac{-1.46}{0.194}=-7.52$

The degrees of freedom are

$df=n_1+n_2-2=9+9-2=16$

The critical value for a left tailed test at a significance level of 0.05 and 16 degrees of freedom is t=-1.746.

The t-statistic is below the critical value, so it lies in the rejection region.

The null hypothesis is rejected.

There is enough evidence to say that the true average heat output of persons with the syndrmoe differs from the true average heat output of non-sufferers.

5 0

2 years ago

Erika worked 18 hours last week and 20 hours this week. If she earns $6 per hour, how much did she earn these two weeks?

Crank

Hi!

If she worked 18 hours last week and 20 hours this week, then she worked 38 hours in total, because 18 + 20 = 38.

If she earns $6 per hour, and she worked for 38 hours, then she got 38 sets of 6, which you can find the answer to by multiplying 38 and 6.

This is essentially 6 + 6 + 6 +...

38 * 6 = $228

So she earned $228 these two weeks.

Hope this helped!

6 0

2 years ago

Read 2 more answers

The body temperatures of adults are normally distributed with a mean of 98.6degrees° F and a standard deviation of 0.60degrees°

Schach [20]

Answer:

97.72% probability that their mean body temperature is greater than 98.4degrees° F.

Step-by-step explanation:

To solve this question, we have to understand the normal probability distribution and the central limit theorem.

Normal probability distribution:

Problems of normally distributed samples can be solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

Central limit theorem:

The Central Limit Theorem estabilishes that, for a random variable X, with mean $\mu$ and standard deviation $\sigma$ , the sample means with size n of at least 30 can be approximated to a normal distribution with mean $\mu$ and standard deviation $s = \frac{\sigma}{\sqrt{n}}$