Download MFM2P1 - Mr. Tjeerdsma

MFM2P1
Introduction to Ratio
Name:
A ratio is a comparison of one number to another. In a classroom, there are 15 boys
and 12 girls. The ratio of boys to girls is 15 to 12. This can be written using different
notation.
Words:
15 to 12
Colon:
15:12
Fraction:
15
12
The order of the ratio is important. If we state the ratio of girls to boys, the ratio is 12 to
15.
The numbers in the ratio are called the terms of the ratio.
1.
2.
Write a ratio for each of the following using colon notation
a)
The number of circles to squares
b)
The number of square to rectangles
c)
The number of rectangles to circles
d)
The number of rectangles to squares
e)
The number of squares to circles to rectangles
Write a ratio to compare the following for our classroom, using fraction notation.
a)
boys to girls
b)
student desks to students
c)
students to teacher
d)
students to student desks
Equivalent Ratios
Equivalent ratios are found by multiplying or dividing both terms of a ratio by the same
number.
Example:
6:9
 6 2 : 9 2
 12 :18
6:9
 6  3: 9  3
 18 : 27
6:9
 6 3:9 3
 2:3
The ratios 6:9, 12:18, 18:27, 2:3 are all equivalent to one another. The ratio 2:3 is in
lowest terms because it cannot be changed to an equivalent ratio using whole numbers
by dividing both terms by the same number.
3.
Write two equivalent ratios for each of the following.
a)
4.
5.
2:5
b)
4:12
c)
8:6
d)
9:5
c)
8:42
d)
15:25
c)
13:2 = ___:6
Find an equivalent ratio in lowest terms.
a)
12:10
e)
6:12:14
b)
12:15
f)
8:20:28
b)
___:24 = 6:12
Find the missing number.
a)
3:5 = 9: ___
d)
4:5:3 = 12:___:___
e)
10:28 = ___:14