Add 15/42 and 21/20
1st number: 15/42, 2nd number: 1 1/20
15/42 + 21/20 is 197/140.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 20 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 42 × 10 = 420,
15/42 = 15 × 10/42 × 10 = 150/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
21/20 = 21 × 21/20 × 21 = 441/420 - Add the two like fractions:
150/420 + 441/420 = 150 + 441/420 = 591/420 - 591/420 simplified gives 197/140
- So, 15/42 + 21/20 = 197/140
In mixed form: 157/140
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