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3 years ago

A plumber is replacing a pipe in a kitchen. The old pipe

Mathematics

2 answers:

Andrew [12]3 years ago

6 0

Answer:

2.57

Step-by-step explanation:

All the plumber has to do is subtract the longer length of the new pipe (10) with the length of the old pipe (7.43) to see how much he needs to cut off.

k0ka [10]3 years ago

5 0

Answer:

He will need to cut off 2.57 inches off of the new pipe.

Step-by-step explanation:

We can calculate how many inches the plumber needs to cut off the 10 inch pipe by finding the difference between the 10 inch pipe and the 7.43 inch pipe.

So let’s subtract 7.43 from 10.

10-7.43 = 2.57

The difference is 2.57 inches, and therefore the plumber will need to cut 2.57 inches off of the new pipe to make it fit where the 7.43 inch pipe used to be.

You might be interested in

Find the slope of the line passing through the points (7, -1) and (2, -8).

Ugo [173]

Answer:

$\frac{4}{5}$

Step-by-step explanation:

We have to use the slope formula: m = slope

(x1, y1) = coordinates of the first point in the line

(x2, y2) = coordinates of the second point in the line

Here, we'll plug into our given points to give; $\frac{7--1}{2--8}$

Solving this, we get, $\frac{8}{10}$ , but we're not done, as this fraction can be reduced.

Diving both sides of the fraction by 2, we get our final answer of $\frac{4}{5}$ .

8 0

3 years ago

the shadow of a statue is 20 feet long while the shadow of a student is 4ft long. if the student is 6ft tall how tall is the sta

zaharov [31]

Answer:

Step-by-step explanation:

ratio and proportion:

x tall 6 ft. tall

4 (x) = 20 (6)

x = 120 / 4

x = 30 ft. tall

3 0

3 years ago

Which value is equivalent to 9^c x 9^-c A. 0 B. 1 C. 1/9^2C D. 9

AleksAgata [21]

Answer:

Step-by-step explanation:

Using the rule of exponents

$a^{m}$ × $a^{n}$ = $a^{(m+n)}$

$a^{0}$ = 1

Given

$9^{c}$ × $9^{-c}$

= $9^{(c-c)}$

= $9^{0}$

= 1 → B

7 0

3 years ago

g A programmer plans to develop a new software system. In planning for the operating system that he will use, he needs to estim

kipiarov [429]

Answer:

a) n= 1045 computers

b) n= 442 computers

c) A. Yes, using the additional survey information from part (b) dramatically reduces the sample size.

Step-by-step explanation:

Hello!

The variable of interest is

X: Number of computers that use the new operating system.

You need to find the best sample size to take so that the proportion of computers that use the new operating system can be estimated with a 99% CI and a margin of error no greater than 4%.

The confidence interval for the population proportion is:

p' ± $Z_{1-\alpha /2}$ * $\sqrt{\frac{p'(1-p')}{n} }$

$Z_{1-\alpha /2}= Z_{0.995}= 2.586$

a) In this item there is no known value for the sample proportion (p') when something like this happens, you have to assume the "worst-case scenario" that is, that the proportion of success and failure of the trial are the same, i.e. p'=q'=0.5

The margin of error of the interval is:

d= $Z_{1-\alpha /2}$ * $\sqrt{\frac{p'(1-p')}{n} }$

$\frac{d}{Z_{1-\alpha /2}} = \sqrt{\frac{p'(1-p)}{n} }$

$(\frac{d}{Z_{1-\alpha /2}})^2 = \frac{p'(1-p')}{n}$

$n * (\frac{d}{Z_{1-\alpha /2}})^2 = p'(1-p')$

$n= [p'(1-p')]*(\frac{Z_{1-\alpha /2}}{d} )^2$

$n=[0.5(1-0.5)]*(\frac{2.586}{0.04} )^2= 1044.9056$

n= 1045 computers

b) This time there is a known value for the sample proportion: p'= 0.88, using the same confidence level and required margin of error:

$n= [p'(1-p')]*(\frac{Z_{1-\alpha /2}}{d} )^2$

$n= [0.88*0.12]*(\frac{{2.586}}{0.04})^2= 441.3681$

n= 442 computers

c) The additional information in part b affected the required sample size, it was drastically decreased in comparison with the sample size calculated in a).

I hope it helps!

4 0

4 years ago

Is 2.1 bigger than 2.20

sergiy2304 [10]

No 2.1 is not bigger than 2.20 because when you add a zero to the end of 2.1 it makes it 2.10.

8 0

3 years ago

Read 2 more answers