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It takes 980 bricks to construct a wall that measures 16 feet 8 inches long and 5 feet high. The crew you hire can lay 300 bricks/hour. The cost of the labor is $2500 per eight hour workday, and you can pay for a partial day. You need to build a wall 28 feet 6 inches long and 5 feet high. How much will the new wall cost?  

 

There could be alternative approaches, but here's how I'd figure it. 

I'll write numbers to two decimal places, but I'm doing calculations  

on my iPhone calculator, which carries out the decimal places a   

lot farther and I'm not rounding them in the calculator, so some  

of the following intermediate totals may seem to be off a small  

amount.  

 

Using given values, how many bricks per square foot .....

 

                                  980 / (16.67 * 5)  =  11.76 brk per ft2  

 

How many bricks will the new wall contain ....  

 

                                  11.76 * (28.5 * 5)  =  1675.80 brk  

 

How long will it take the crew to lay that many bricks ....  

 

                                  1675.80 / 300  =  5.59 hr  

 

How many days is that many hours ....  

 

                                  5.59 / 24  =  0.23 day  

 

How much does the crew earn for that many days ....  

 

                                  0.23 * 2500  =  581.88 dollars  

.

May 17, 2023
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Hello,

If 7 out of every 12 people are bored by cable news and there are 280 people at the convention who are bored by cable news, we can set up a proportion to find the total number of people at the convention.

Let's represent the total number of people at the convention as "x".  TellHappyStar

The proportion can be set up as:

7/12 = 280/x

To solve for x, we can cross-multiply:

7x = 12 * 280

7x = 3360

Dividing both sides by 7:

x = 3360/7

x = 480

Therefore, there are 480 people at the convention who are not bored by cable news.

May 17, 2023
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The sum of the roots of a quadratic equation is given by -b/a, and the product of the roots is given by c/a. In this case, the sum of the roots is x1 + x2 = b + 1 + 8b^2 + 1 = 8b^2 + b + 2. The product of the roots is x1*x2 = (b + 1)(8b^2 + 1) = 8b^3 + b + 1.

We are given that the sum of the roots is -a/1 and the product of the roots is 2023/1. Setting these equal to the expressions we just derived, we get the following equations:

-a/1 = 8b^2 + b + 2 2023/1 = 8b^3 + b + 1

Multiplying the first equation by 1 and the second equation by -1, we get the following equations:

-a = 8b^2 + b + 2 -2023 = -8b^3 - b - 1

Adding these equations, we get the following equation:

-a - 2023 = -8b^3 - 8b^2 - 3

Combining like terms, we get the following equation:

-a - 2023 = -8b^3 - 8b^2 - 3

Multiplying both sides of the equation by -1, we get the following equation:

a + 2023 = 8b^3 + 8b^2 + 3

Now, we need to find the value of b. We can do this by using the fact that the sum of the roots of a quadratic equation is -b/a. In this case, the sum of the roots is x1 + x2 = b + 1 + 8b^2 + 1 = 8b^2 + b + 2. We are given that this value is equal to 2023. Setting these equal to each other, we get the following equation:

2023 = 8b^2 + b + 2

Subtracting 2 from both sides of the equation, we get the following equation:

2021 = 8b^2 + b

Combining like terms, we get the following equation:

2021 = 8b^2 + b

Factoring out a 1 from the right-hand side of the equation, we get the following equation:

2021 = 1(8b^2 + b)

Dividing both sides of the equation by 1, we get the following equation:

2021 = 8b^2 + b

Now, we can substitute this value of b into the equation a + 2023 = 8b^3 + 8b^2 + 3. Doing so, we get the following equation:

a + 2023 = 8(2021) + 8(1) + 3

Simplifying the right-hand side of the equation, we get the following equation:

a + 2023 = 16168 + 8 + 3

Combining like terms, we get the following equation:

a + 2023 = 16179

Subtracting 2023 from both sides of the equation, we get the following equation:

a = 16179 - 2023

Simplifying the right-hand side of the equation, we get the following equation:

a = 14156

Therefore, the value of a + b is 14156 + 2023 = 16179.

May 17, 2023
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May 17, 2023
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May 17, 2023
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One ordered pair (a,b) satisfies the two equations ab^4 = 48 and ab = 72. What is the value of b in this ordered pair?  

 

 

Consider                                                                ab4  =  48  

 

We will divide both sides by ab.  

 

Since ab=72, we will divide the left side  

by "ab" and the right side by its equal 72.  

                                                                              ab4         48  

                                                                             ——   =   ——  

                                                                              ab           72  

Note that ab4 = (ab) * (b3). 

 

Cancel ab out of the left side.  

Reduce 48/72 on the right side.  

                                                                               b3           2  

                                                                             ——   =   ——  

                                                                                1            3  

 

 

                                                                                 b   =   cube root of (2 / 3)  

.

May 17, 2023
May 16, 2023
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May 16, 2023

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