A tree is 3 ft tall casts a shadow that is 2 ft long. Find the length of the shadow that a 6 ft tree costs.

Which are lines that will intersect? Which are perpendicular lines? Which are skew lines?

sashaice [31]

Lines that intersect are intersecting or crossing lines.
Perpendicular lines are lines that cross at a 90 degree angle.
Skew lines are lines that are non-coplanar and don’t intersect.

8 0

3 years ago

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A patient needs to receive 1 teaspoon of a medication per day for one week. How many milliliters of the medication must be dispe

BabaBlast [244]

Answer:

B. 35 milliliters,

Step-by-step explanation:

1 teaspoonful = 5 mls so the total volume of medicine

= 7 * 5

= 35 milliliters.

6 0

3 years ago

The amount of time the husband and the wife spend on house work is measured for 15 women and their 15 husbands. For the wives th

dolphi86 [110]

Answer:

The value of the test statistic is z = -0.877.

Step-by-step explanation:

Testing the difference in mean time spent on housework between husbands and wives.

At the null hypothesis, we test if there is no difference, that is, the subtraction of the means is 0:

$H_0: \mu_H - \mu_W = 0$

At the alternate hypothesis, we test if there is a difference, that is, the subtraction of the means is different from 0.

$H_1: \mu_H - \mu_W \neq 0$

The test statistic is:

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

In which X is the sample mean, $\mu$ is the value tested at the null hypothesis, and s is the standard error.

0 is tested at the null hypothesis:

This means that $\mu = 0$

For the wives the mean was 7 hours/week and for the husbands the mean was 4.5 hours/week. The standard deviation of the differences in time spent on house work was 2.85.

This means that $X = 4.5 - 7 = -2.5, s = 2.85$

What is the value of the test statistic for testing the difference in mean time spent on housework between husbands and wives?

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

$z = \frac{-2.5 - 0}{2.85}$

$z = -0.877$

The value of the test statistic is z = -0.877.

4 0

3 years ago

What are the answers for both of those if you get it right I’ll also give you brainliest answer comment

tangare [24]

Answer:

answer 1, 135

Step-by-step explanation:

6 0

3 years ago

How many terms of the arithmetic sequence {1,22,43,64,85,…} will give a sum of 2332? Show all steps including the formulas used

MA_775_DIABLO [31]

There's a slight problem with your question, but we'll get to that...

Consecutive terms of the sequence are separated by a fixed difference of 21 (22 = 1 + 21, 43 = 22 + 21, 64 = 43 + 21, and so on), so the n-th term of the sequence, a (n), is given recursively by

• a (1) = 1

• a (n) = a (n - 1) + 21 … … … for n > 1

We can find the explicit rule for the sequence by iterative substitution:

a (2) = a (1) + 21

a (3) = a (2) + 21 = (a (1) + 21) + 21 = a (1) + 2×21

a (4) = a (3) + 21 = (a (1) + 2×21) + 21 = a (1) + 3×21

and so on, with the general pattern

a (n) = a (1) + 21 (n - 1) = 21n - 20

Now, we're told that the sum of some number N of terms in this sequence is 2332. In other words, the N-th partial sum of the sequence is

a (1) + a (2) + a (3) + … + a (N - 1) + a (N) = 2332

or more compactly,

$\displaystyle\sum_{n=1}^N a(n) = 2332$

It's important to note that N must be some positive integer.

Replace a (n) by the explicit rule:

$\displaystyle\sum_{n=1}^N (21n-20) = 2332$

Expand the sum on the left as

$\displaystyle 21 \sum_{n=1}^N n-20\sum_{n=1}^N1 = 2332$

and recall the formulas,

$\displaystyle\sum_{k=1}^n1=\underbrace{1+1+\cdots+1}_{n\text{ times}}=n$

$\displaystyle\sum_{k=1}^nk=1+2+3+\cdots+n=\frac{n(n+1)}2$

So the sum of the first N terms of a (n) is such that

21 × N (N + 1)/2 - 20N = 2332

Solve for N :

21 (N ² + N) - 40N = 4664

21 N ² - 19 N - 4664 = 0

Now for the problem I mentioned at the start: this polynomial has no rational roots, and instead

N = (19 ± √392,137)/42 ≈ -14.45 or 15.36

so there is no positive integer N for which the first N terms of the sum add up to 2332.

4 0

2 years ago