Add 72/20 and 28/42
1st number: 3 12/20, 2nd number: 28/42
72/20 + 28/42 is 64/15.
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,
72/20 = 72 × 21/20 × 21 = 1512/420 - Likewise, for the 2nd fraction, since 42 × 10 = 420,
28/42 = 28 × 10/42 × 10 = 280/420 - Add the two like fractions:
1512/420 + 280/420 = 1512 + 280/420 = 1792/420 - 1792/420 simplified gives 64/15
- So, 72/20 + 28/42 = 64/15
In mixed form: 44/15
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