Add 3/28 and 21/20
1st number: 3/28, 2nd number: 1 1/20
3/28 + 21/20 is 81/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 20 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 28 × 5 = 140,
3/28 = 3 × 5/28 × 5 = 15/140 - Likewise, for the 2nd fraction, since 20 × 7 = 140,
21/20 = 21 × 7/20 × 7 = 147/140 - Add the two like fractions:
15/140 + 147/140 = 15 + 147/140 = 162/140 - 162/140 simplified gives 81/70
- So, 3/28 + 21/20 = 81/70
In mixed form: 111/70
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