Add 21/20 and 72/42
1st number: 1 1/20, 2nd number: 1 30/42
21/20 + 72/42 is 387/140.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 42 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 20 × 21 = 420,
21/20 = 21 × 21/20 × 21 = 441/420 - Likewise, for the 2nd fraction, since 42 × 10 = 420,
72/42 = 72 × 10/42 × 10 = 720/420 - Add the two like fractions:
441/420 + 720/420 = 441 + 720/420 = 1161/420 - 1161/420 simplified gives 387/140
- So, 21/20 + 72/42 = 387/140
In mixed form: 2107/140
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