Add 21/63 and 42/81
21/63 + 42/81 is 23/27.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 63 and 81 is 567
Next, find the equivalent fraction of both fractional numbers with denominator 567 - For the 1st fraction, since 63 × 9 = 567,
21/63 = 21 × 9/63 × 9 = 189/567 - Likewise, for the 2nd fraction, since 81 × 7 = 567,
42/81 = 42 × 7/81 × 7 = 294/567 - Add the two like fractions:
189/567 + 294/567 = 189 + 294/567 = 483/567 - 483/567 simplified gives 23/27
- So, 21/63 + 42/81 = 23/27
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