Answer:
a) 1.8 
b) 3.6 
Step-by-step explanation:
Conversion and calculation of areas
The area of a rectangle is A=wh, where w is the width and h is the height. There are 3 feet in one yard
a)
We are told Kalie put 6 stickers, each one of 1/2 centimeters (0.5 cm) wide by 3/5 (0.6 cm) centimeter long. The area of one sticker is
A=(0.5)(0.6)=0.3 
Assuming there is no overlapping, the 6 stickers have a total area
6*0.3
=1.8 
b)
Each of Elana's wrapping papers measures 2/5 yards long and 1/4 yard wide. Converting them to feet we have
long=2/5*3=1.2 feet
wide=1/4*3=0.75 feet
Area of each paper=1.2 feet*0.75 feet=0.9 
Area of the entire board, assuming no overlapping and no space left uncovered=4*0.9 
Area of board=3.6 
$5.25, because if you multiply $6 by 7/8(fraction form), you get $5.25
Get n to one side
-1/5=-2/5n
divide both sides by -2/5
n=1/2
The equation in standard form would be,

All you have to do is move -2/7x to the other side.
Hope this helped
:D
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