Lesson 1 operations with fractions part 2 (notes)
- 1. Adding & Subtracting
2
4
5
−1
5
6
=
LCD = 30
2
4
5
= 2
30
1
5
6
=1
30
24
25
31
30
1
1
30
• Find LCD if denominators are
unlike.
• Find equivalent fractions using
the LCD.
• If the first numerator is smaller
than the second numerator,
rename the fractions as
Improper Fractions.
• Subtract numerators. Keep the
denominator.
• Simplify.
84
30
55
30
=
=
=
=
- 2. Multiplying
• Rename fractions as
Improper Fraction if needed.
• Multiply numerator by
numerator.
• Multiply denominator by
denominator.
• Simplify.
1
2
5
•2
3
4
=
1
2
5
•2
3
4
=
7
5
•
11
4
7
5
•
11
4
=
77
7
5
•
11
4
= 77
20
3
17
20
- 3. Dividing
• Rename fractions as
Improper Fraction if needed.
• Keep the first fraction.
• Change division (÷) to
multiplication (•).
• Flip the second fraction to
make its reciprocal.
• Multiply the fractions.
• Simplify.
2
1
4
÷1
2
5
=
2
1
4
÷1
2
5
=
9
4
÷
7
5
9
4
45
28
=1
17
28
9
4
• =
5
7
=