Add 21/27 and 20/63
21/27 + 20/63 is 23/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 27 and 63 is 189
Next, find the equivalent fraction of both fractional numbers with denominator 189 - For the 1st fraction, since 27 × 7 = 189,
21/27 = 21 × 7/27 × 7 = 147/189 - Likewise, for the 2nd fraction, since 63 × 3 = 189,
20/63 = 20 × 3/63 × 3 = 60/189 - Add the two like fractions:
147/189 + 60/189 = 147 + 60/189 = 207/189 - 207/189 simplified gives 23/21
- So, 21/27 + 20/63 = 23/21
In mixed form: 12/21
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