Multiplication of Fractions
To multiply fractions, multiply the numerators together and multiply the denominators together.
Simplify the result if possible. Whole numbers should first be written as fractions.
Example 1.21
Solve:
15
×
1011
Solution:
Multiply numerators and denominators:
1 × 105 × 11
=
1055
Simplify:
211
Example 1.22
Solve:
6 × 23
Solution:
Write 6 as a fraction:
61
Multiply:
6 × 21 × 3
=
123
Simplify: 4
Example 1.23
Simplify:
5 16
×
1 12
Solution:
Convert to improper fractions:
316
×
32
Multiply:
9312
Simplify:
7 34
Exercise 1.10
1. Evaluate each of the following:
Type answers as a/b or mixed numbers as a/b/c
(a)
45
×
516
Answer:
(b) 4 ×
23
Answer:
(c) 6
14
×
1625
Answer:
(d) 2
217
× 1
13
Answer:
(a) 1/4
(b) 8/3 or 2/2/3
(c) 4
(d) 56/17 or 3/5/17
Working:
(a) (4 × 5) ÷ (5 × 16) = 20/80 = 1/4
(b) 4/1 × 2/3 = 8/3 = 2/2/3
(c) 25/4 × 16/25 = 4
(d) 36/17 × 4/3 = 144/51 = 56/17 = 3/5/17
Speed Round: Multiplication of Fractions
Rules:
Fractions: a/b
Mixed numbers: a/b/c (means a + b/c)
Time: 0 seconds