Add 21/81 and 4/7
21/81 + 4/7 is 157/189.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 7 is 567
Next, find the equivalent fraction of both fractional numbers with denominator 567 - For the 1st fraction, since 81 × 7 = 567,
21/81 = 21 × 7/81 × 7 = 147/567 - Likewise, for the 2nd fraction, since 7 × 81 = 567,
4/7 = 4 × 81/7 × 81 = 324/567 - Add the two like fractions:
147/567 + 324/567 = 147 + 324/567 = 471/567 - 471/567 simplified gives 157/189
- So, 21/81 + 4/7 = 157/189
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