Answer:these weren’t all right
Step-by-step explanation:
From the information we have, we know that each book costs 1.20 dollars. So we shall say this price is at 100% .
Now we need to form an equation to get the percentage when the books are sold at 0.80 dollars.
100% = 1.20
x = 0. 80
Where x is the new percentage when the sale is at 0.80 dollars.
We cross multiply the equation:
1.20 *x = 0.80 * 100
1.2x = 80
x = 80/1.2
x = 66.7%
Round off 66.7 to the nearest tenth we get 67%
The notebooks are sold at 67% (of the original cost).
First we have to find length of 1 side of the square. We can use formula for area of the square. A=a*a ==>

where a is length of the side.
From this formula we can find

a=

Now we just have to multiply it by 4, because there are 4 sides.
81*4=324 - its the answer
Answer:
7/20
Step-by-step explanation:
We need to find a common denominator in this equation, which would be 20. By changing the fractions to this denominator you would simply get 15-8 which equals 7