Answer:
Let p represent the # of pages in the book. Then, Nora has already read 0.30p pages and has 0.70p pages left to read.
If she reads 25% pages/night, that means reading 0.25(0.70)p pages per night, or 17.5 pages/night. If 28% p/n, that means 0.28(0.70)p pages/night, or 19.6p pages/night.
How many nights will it take Nora to finish the book if she reads 25% of 7/10 of the book per night? Without any calculations, we can answer this by "4 nights, since she reads 1/4 of the unread portion of the book per night."
If she reads 28% of 7/10 of the book per night, that will require fewer nights:
First night: 28%
Second night: 28%
Third night: 28%
Total: 3(28%) = 84%
This leaves 16% to read on the final night.
This is one interpretation of what I think is a poorly worded question.
The author of this question might have meant reading 25% of the remaining unread pages per night, which leads to a different answer.
X = 4y
3x - y = 70
substitute the x in the second equation with the other half of the first equation.
3(4y) - y = 70
12y - y = 70
11y = 70
y = 6.36 repeating, or 6 4/11
now use this to solve first equation
x = 4 (6 4/11)
x = 25.45 repeating
done
They are integers that follow one right after another. For example the set {1,2,3,4,5} represents consecutive numbers. Another example would be {9,10,11,12,13}
In general, if x is some integer, then x+1 is the next integer right after x, and x+2 is right after x+1 and so on. The list is {x, x+1, x+2, x+3, ...} representing any general set of consecutive numbers.
All you have to do is plug in the value of X in each expression for the sides of the triangle. Then after you figure out the values for the sides of the triangle in feet. Add the sides together to find the perimeter of the triangle.
