Add 25/81 and 42/21
1st number: 25/81, 2nd number: 2 0/21
25/81 + 42/21 is 187/81.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 21 is 567
Next, find the equivalent fraction of both fractional numbers with denominator 567 - For the 1st fraction, since 81 × 7 = 567,
25/81 = 25 × 7/81 × 7 = 175/567 - Likewise, for the 2nd fraction, since 21 × 27 = 567,
42/21 = 42 × 27/21 × 27 = 1134/567 - Add the two like fractions:
175/567 + 1134/567 = 175 + 1134/567 = 1309/567 - 1309/567 simplified gives 187/81
- So, 25/81 + 42/21 = 187/81
In mixed form: 225/81
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