Brandon has a playlist with 83 hip-hop and pop songs. There are 15 more hip-hop songs than pop songs. How many pop songs are on
1 answer:
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Answer:
Explanation:
The complete question is:
<em>A hole the size of a photograph is cut from a red piece of paper to use in a picture frame.</em>
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<em>On a coordinate plane, 2 squares are shown. The photograph has points (-3, -2), (- 2, 2), (2, 1), and (1, -3). The red paper has points (- 4, 4), (4, 4), (4, -4), and (-4, -4).</em>
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<em>What is the area of the piece of red paper after the hole for the photograph has been cut?</em>
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<h2><em>Solution</em></h2><em />
The area of the piece of redpaper after the hole has been cut is equal to the area of the big square less the area of the small rectangle.
<u>1. Area of the big rectangle</u>
Vertices:
- <em>(- 4, 4) </em>
- <em>(4, 4)</em>
- <em>(4, -4)</em>
- <em>(-4, -4)</em>
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The side length is the distance between two consecutive vertices:
The two points (-4,4) and (4,4) has the same y-coordinate, thus the length is just the absolute value of the difference of the x-coordinates:
The area of this square is
<u>2. Area of the small square</u>
Vertices:
- <em>(-3, -2)</em>
- <em>(- 2, 2) </em>
- <em>(2, 1)</em>
- <em>(1, -3)</em>
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To find the side length use the distance formula for two consecutive points, for instance (2,1) and (-2,2):
The area is:
<u>3. Area of the piece of red paper after the holw for the photograph has been cut:</u>
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Find the difference:
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Answer:
4 liters of 60% solution; 2 liters of 30% solution
Step-by-step explanation:
I like to use a simple, but effective, tool for most mixture problems. It is a kind of "X" diagram as in the attachment.
The ratios of solution concentrations are 3:6:5, so I've used those numbers in the diagram. The constituent solutions are on the left; the desired mixture is in the middle, and the numbers on the other legs of the X are the differences along the diagonals: 6 - 5 = 1; 5 - 3 = 2. This tells you the ratio of 60% solution to 30% solution is 2 : 1.
These ratio units (2, 1) add to 3. We want 6 liters of mixture, so we need to multiply these ratio units by 2 liters to get the amounts of constituents needed. The result is 4 liters of 60% solution and 2 liters of 30% solution.
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If you're writing equations, it often works well to let the variable represent the quantity of the greatest contributor—the 60% solution. Let the volume of that (in liters) be represented by v. Then the total volume of iodine in the mixture is ...
... 0.60·v + 0.30·(6 -v) = 0.50·6
... 0.30v = 0.20·6 . . . . subtract 0.30·6, collect terms
... v = 6·(0.20/0.30) = 4 . . . . divide by the coefficient of v
4 liters of 60% solution are needed. The other 2 liters are 30% solution.
