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3 years ago

A building engineer analyzes a concrete column with a circular cross section. The circumference of the column is 18π meters.

Mathematics

1 answer:

Whitepunk [10]3 years ago

8 0

Answer:

$A=81\pi\ m^{2}$

Step-by-step explanation:

Step 1

Find the radius of the circular cross section

we know that

The circumference is equal to

$C=2\pi r$

we have

$C=18\pi\ m$

substitute and solve for r

$18\pi=2\pi r$

simplify

$18=2 r$

$r=9\ m$

Step 2

Find the area of the circular cross section

The area of the circle is equal to

$A=\pi r^{2}$

we have

$r=9\ m$

substitute

$A=\pi (9)^{2}$

$A=81\pi\ m^{2}$

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Awarding road contracts. A state Department of Transportation (DOT) recently claimed that each of five bidders received equal co

Sveta_85 [38]

Answer:

a) Hence, the probability of this event occurring if, in fact, the DOT's claim is true

= 3/10 = 0.3

Step-by-step explanation:

a) The concept applied here is combinatorics ; nCr = n!/(n - r)!r!

we are told that out of 5bidders, Three of the bidders were large construction conglomerates

and two were small specialty contractors.

selecting two recipients with tree of the bidders were large construction conglomerates 3C2

= 3!/(3-2)!2!

= 3

Similarly, selecting the two small casualty contractor from the total of 5bidders = 5C2

= 5!/(5-2)!2!

= 10

Hence, the probability of this event occurring if, in fact, the DOT's claim is true

= 3/10 = 0.3

b) if DOTs claim is not true ( probability of failure) = 1 - 0.3

= 0.7 , this value implies that the probability 0.3 is largely compatible and a compliment of the 0.7 and as such it is consistent with the DOTs claim that the selection was random.

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3 years ago

Melissa has scored 83 , 84 , 93 , 77 , and 85 on her previous five tests. what score does she need on her next test so that her

pantera1 [17]

83 x 6 = 498

all six of her scores need to equal at least 498 for an 83 average

83 + 84 + 93 + 77 + 85 = 422

498-422 = 76

she needs a 76

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3 years ago

An architectural drawing lists the scale as 1/4" = 1'. If a bedroom measures 634" by 412" on the drawing, how large is the bedro

Rudiy27

and the answer should be 18 x 27. The answers were reversed.

Step-by-step explanation:

basically you can do (6x4) + 3 = 27

and (4x4) + 2 = 18.

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3 years ago

In the penny game exercise, why do you think it takes longer for one person to flip five batches of two pennies then one batch o

Nataly [62]

It takes longer for one person to flip five batches of two pennies than one batch of ten pennies, mainly for a simple reason: although 5 x 2 is equal to 10, that is, it will take the same time to flip the coins, 5 batches is greater than 1 batch, which will take longer to manipulate each of these, increasing the total time.

Learn more about maths in brainly.com/question/21477139

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3 years ago

a television normally sells for $499 what is now discounted 25%. The sales tax rate is 6.5%. What is the total cost of televisio

matrenka [14]

Hmmm what is now discounted? well, let's assume it sells normally for 499 and is discounted today at 25%, how much is that?

well, if we take 499 to be the 100, how much is 25%?

$\bf \begin{array}{ccll}
amount&\%\\
\text{\textemdash\textemdash\textemdash}&\text{\textemdash\textemdash\textemdash}\\
499&100\\
d&25
\end{array}\implies \cfrac{499}{d}=\cfrac{100}{25} \cfrac{499\cdot 25}{100}=d
\\\\\\
124.75=d\qquad \textit{so the new price is }499-124.75\implies 374.25$

now, applying the sales tax to the discounted price.

if we take 374.25 to be the 100%, how much is 6.5%?

$\bf \begin{array}{ccll}
amount&\%\\
\text{\textemdash\textemdash\textemdash}&\text{\textemdash\textemdash\textemdash}\\
374.25&100\\ t&6.5
\end{array}\implies \cfrac{374.25}{t}=\cfrac{100}{6.5}\implies \cfrac{374.25\cdot 6.5}{100}=t$

so, the total cost will then be 374.25 + t.

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4 years ago