Help me please what do they mean?

Select the correct answer, and simplify the expression -3÷(-2/5). A. -7 1/2

aliina [53]

Answer:

D

Step-by-step explanation:

Given

- 3 ÷ - $\frac{2}{5}$

Leave the first number, change division to multiplication and turn the fraction upside down, that is

= - 3 × - $\frac{5}{2}$

= $\frac{3(5)}{2}$

= $\frac{15}{2}$

= 7 $\frac{1}{2}$ → D

3 0

3 years ago

What is the quotient of 33,075 divided by<br> 35?

Reil [10]

Quotient=Division.33075/35=945
945 is your answer.

5 0

3 years ago

Read 2 more answers

It appears that people who are mildly obese are less active than leaner people. One study looked at the average number of minute

NemiM [27]

Answer:

a) 10.93% probability that the mean number of minutes of daily activity of the 5 mildly obese people exceeds 420 minutes.

b) 99.22% probability that the mean number of minutes of daily activity of the 5 lean people exceeds 420 minutes.

Step-by-step explanation:

The Central Limit Theorem estabilishes that, for a random variable X, with mean $\mu$ and standard deviation $\sigma$ , a large sample size can be approximated to a normal distribution with mean $\mu$ and standard deviation $\frac{\sigma}{\sqrt{n}}$ .

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.

Mildly obese

Normally distributed with mean 373 minutes and standard deviation 67 minutes. So $\mu = 373, \sigma = 67$

A) What is the probability that the mean number of minutes of daily activity of the 5 mildly obese people exceeds 420 minutes?

So $n = 5, s = \frac{67}{\sqrt{5}} = 29.96$

This probability is 1 subtracted by the pvalue of Z when X = 410.

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

$Z = \frac{410 - 373}{29.96}$

$Z = 1.23$

$Z = 1.23$ has a pvalue of 0.8907.

So there is a 1-0.8907 = 0.1093 = 10.93% probability that the mean number of minutes of daily activity of the 5 mildly obese people exceeds 420 minutes.

Lean

Normally distributed with mean 526 minutes and standard deviation 107 minutes. So $\mu = 526, \sigma = 107$

B) What is the probability that the mean number of minutes of daily activity of the 5 lean people exceeds 420 minutes?

So $n = 5, s = \frac{107}{\sqrt{5}} = 47.86$

This probability is 1 subtracted by the pvalue of Z when X = 410.

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

$Z = \frac{410 - 526}{47.86}$

$Z = -2.42$

$Z = -2.42$ has a pvalue of 0.0078.

So there is a 1-0.0078 = 0.9922 = 99.22% probability that the mean number of minutes of daily activity of the 5 lean people exceeds 420 minutes.

7 0

3 years ago

A photocopy machine can print 405 copies in 9 minutes. what is the unit rate the machine can produce in 1 minute

Zolol [24]

Answer:45

Step-by-step explanation: divide 405 by 9

3 0

3 years ago

How do i solve 12×+9=10×1

s2008m [1.1K]

Answer:

Step-by-step explanation:

Unfortunately, your " 12×+9=10×1 " can be interpreted in more than one way. The symbol " × " should be used ONLY to indicate multiplication. Thus, " 12× " reads as ' 12x.' Then we have: 12x + 9 = 10. Unsure of what you meant by " 10×1". So I will treat your "10×1" as simply '10.'

Then we have 12x + 9 = 10, which reduces to 12x = 1 if we subtract 9 from both sides.

12x = 1 yields x = 1/12.

If this is not the result you expected, please go back to the original problem and share it as accurately as you can.

6 0

3 years ago