Download Grade 8 Math Assignment: Fractions, Decimals and Percents

Grade 8 Math Assignment: Fractions, Decimals
and Percents
Part A: Representing Percents Less than 1
1. Inflation rates are often expressed as a fractional percent that is less than 1.
a. On a hundred grid, shade one small square red. What fraction of the grid is red?
b. Express the fraction as a decimal and then as a percent.
1
of a small square blue. What percent of the grid is blue?
2
Explain what this means. Express the percent as a decimal.
2. On the same grid shade
3. On a new hundred grid, shade squares to represent these fractional percents. Use
different colours.
a.
1
%
3
b.
1
%
4
c.
1
%
5
d.
2
%
5
4. On another hundred grid, shade squares to show 40%, 4%, and 0.4%, using
different colours.
a. Express each as a decimal and as a fraction in simplest form.
b. How do 40%, 4%, and 0.4% differ in meaning?
Part B: Representing Percents Between 1 and 100
Bank rates for savings accounts, loans and mortgages are often expressed as a
1
fractional percent. Suppose the bank pays 3 % annual interest.
2
1. On a hundred grid shade three small squares.
a. What percent of the grid is shaded? Write the percent as a decimal.
b. On a second hundred grid shade 4 small squares. What percent of the grid is
shaded? Write the percent as a decimal.
1
c. On a third hundred grid, shade 3 % of the grid. Write the percent as a decimal.
2
2. Copy and complete the table.
Fractional Percent
3
6 %
4
1
11 %
5
Percent
Expressed with a
Decimal
6.75%
Fraction with 100
in the
Denominator
6.75
100
Decimal
0.0675
19.25%
0.085
1
3. Suppose you deposit $100 into a bank account that pays 3 % interest annually.
2
a. How much is 3% of $100? How much is 4% of $100?
b. Express each percent as a decimal and write a multiplication sentence for
each part of a).
c. Use your answer in part a) to predict the amount of interest you would
earn in one year.
1
d. Explain how you can use the decimal equivalent of 3 % of $100.
2
Part C: Represent Percents Greater than 100
1. Use 4 linking cubes (or blocks, marbles, anything with the same shape and size) to
build a 4 by 1 shape. This shape represents 100%.
2. Build a second shape using only 50% of the pieces used in the shape from 1.
b. How can you tell you used the correct number of linking cubes?
3. Build a third shape that uses 50% more pieces than the original shape. This shape
is 150% the size of the original shape or 1.5 times larger.
4.
a. How many linking cubes would you need to build a fourth rectangular prism that
uses 100% more linking cubes than the original rectangular prism? Build it.
b. What percent of the original is your new prism? What would be another way to
say this?
5. Let
represent 100%. Copy and complete the chart from the book.
Percent of Original
Drawing
Number of Cubes
50%
2
100%
4
125%
6
200%
250%
300%
6. John’s tomato plant grew 250% of its original size in 3 months. How can he
represent the percent using a diagram and in words or numbers?
HUNDREDS GRIDS