Add 21/28 and 18/20
21/28 + 18/20 is 33/20.
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,
21/28 = 21 × 5/28 × 5 = 105/140 - Likewise, for the 2nd fraction, since 20 × 7 = 140,
18/20 = 18 × 7/20 × 7 = 126/140 - Add the two like fractions:
105/140 + 126/140 = 105 + 126/140 = 231/140 - 231/140 simplified gives 33/20
- So, 21/28 + 18/20 = 33/20
In mixed form: 113/20
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