Add 72/20 and 42/28
1st number: 3 12/20, 2nd number: 1 14/28
72/20 + 42/28 is 51/10.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 28 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 20 × 7 = 140,
72/20 = 72 × 7/20 × 7 = 504/140 - Likewise, for the 2nd fraction, since 28 × 5 = 140,
42/28 = 42 × 5/28 × 5 = 210/140 - Add the two like fractions:
504/140 + 210/140 = 504 + 210/140 = 714/140 - 714/140 simplified gives 51/10
- So, 72/20 + 42/28 = 51/10
In mixed form: 51/10
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