Answer:
133 pieces of 15cm can be cut from the ribbon.
Step-by-Step Explanation:
Length of ribbon = 20 meters
Length needed to be cut = 15 cm
We will convert meters into centimeters.
1 meter = 100 cm
20 meters = 2000 cm
Number of pieces = 
Number of pieces = 133.33
Rounding off to nearest whole number = 133
Hence,
133 pieces of 15cm can be cut from the ribbon.
-10.2 - 12.85 which would be -23.05
the 10.2 is negative because it is below zero
Let
x---------> represent the number of miles Troy's has driven
y--------> represent the amount of gas in Troy's truck
we know that
the equation that represents the amount of gas, y, in troy' s truck after driving a certain number of miles, x is

where
m is the slope---------> 
in this problem the slope is equal to 
it's negative because the tank is going to be consumed
assuming he starts with a full tank

substitute in the formula above

therefore
the answer is
the equation 