Add 10/21 and 21/27
10/21 + 21/27 is 79/63.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 27 is 189
Next, find the equivalent fraction of both fractional numbers with denominator 189 - For the 1st fraction, since 21 × 9 = 189,
10/21 = 10 × 9/21 × 9 = 90/189 - Likewise, for the 2nd fraction, since 27 × 7 = 189,
21/27 = 21 × 7/27 × 7 = 147/189 - Add the two like fractions:
90/189 + 147/189 = 90 + 147/189 = 237/189 - 237/189 simplified gives 79/63
- So, 10/21 + 21/27 = 79/63
In mixed form: 116/63
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