If the total number of points in the class
is 800, how many points is the class project
worth?
Looking at the pie chart, notice how the class
project is green.
Therefore the class project is 20% of the
grade.
Therefore the class project is worth 20% of
800 points.
So to answer the question, we need to determine
what is 20% of 800.
We will show how to do this 2 ways.
First to find the percent of a whole, step
one is to write the percent as a decimal by
moving the decimal point two places to the
left.
Then step 2, we multiply the percent as a
decimal by the whole amount.
So let's convert 20% to a decimal.
Right now the decimal is to the right of the
zero.
Move it left two places: one, two.
Which will give us point two zero or just
just zero point 2.
So we have zero point two times 800.
This product will give us 20% of 800, which
is equal to 160.
Which means the class project is worth 160
points.
We can also answer this question using the
percent equation: percent times base equals
amount.
Where we know the percent is 20%.
Because the question reads, "What is 20% of
800?"
800 is the whole amount.
Therefore 800 is the base.
The unknown is the part of the 800 or part
of the whole, which would be the amount.
Let's use the variable a for the amount.
Now if we set up the equation, we would get
the percent, which is 20% times the base,
which is 800, equals a.
We convert the 20% to a decimal, which would
be zero point 2.
So we have 0.2 times 800 equals a.
Notice how this is the same product that we
used in our first method.
We know a equals 160, telling us the class
project is worth 160 points.
I hope you found this helpful.
