1 Convert
5
2
3
5
3
2
to improper fraction. Use this rule:
a
b
c
=
a
c
+
b
c
a
c
b
=
c
ac+b
5
×
3
+
2
3
−
3
3
4
=
1
+
2
3
+
3
4
3
5×3+2
−3
4
3
=1+
3
2
+
4
3
2 Simplify
5
×
3
5×3 to
1
5
15
1
5
+
2
3
−
3
3
4
=
1
+
2
3
+
3
4
3
15+2
−3
4
3
=1+
3
2
+
4
3
3 Simplify
1
5
+
2
15+2 to
1
7
17
1
7
3
−
3
3
4
=
1
+
2
3
+
3
4
3
17
−3
4
3
=1+
3
2
+
4
3
4 Convert
3
3
4
3
4
3
to improper fraction. Use this rule:
a
b
c
=
a
c
+
b
c
a
c
b
=
c
ac+b
1
7
3
−
3
×
4
+
3
4
=
1
+
2
3
+
3
4
3
17
−
4
3×4+3
=1+
3
2
+
4
3
5 Simplify
3
×
4
3×4 to
1
2
12
1
7
3
−
1
2
+
3
4
=
1
+
2
3
+
3
4
3
17
−
4
12+3
=1+
3
2
+
4
3
6 Simplify
1
2
+
3
12+3 to
1
5
15
1
7
3
−
1
5
4
=
1
+
2
3
+
3
4
3
17
−
4
15
=1+
3
2
+
4
3
7 Find the Least Common Denominator (LCD) of
1
7
3
,
1
5
4
3
17
,
4
15
Method 1: By Listing Multiples
List out all multiples of each denominator, and find the first common one.
Multiples of 3 : 3, 6, 9, 12, ...
Multiples of 4 : 4, 8, 12, ...
Therefore, the LCD is
1
2
12.
Method 2: By Prime Factors
List all prime factors of each denominator, and find the union of these primes.
Prime Factors of 3 : 3
Prime Factors of 4 : 2, 2
Therefore, the LCD is
2
×
2
×
3
=
1
2
2×2×3=12.
