Add 21/20 and 25/28
1st number: 1 1/20, 2nd number: 25/28
21/20 + 25/28 is 68/35.
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,
21/20 = 21 × 7/20 × 7 = 147/140 - Likewise, for the 2nd fraction, since 28 × 5 = 140,
25/28 = 25 × 5/28 × 5 = 125/140 - Add the two like fractions:
147/140 + 125/140 = 147 + 125/140 = 272/140 - 272/140 simplified gives 68/35
- So, 21/20 + 25/28 = 68/35
In mixed form: 133/35
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