Add 21/28 and 4/20
21/28 + 4/20 is 19/20.
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,
4/20 = 4 × 7/20 × 7 = 28/140 - Add the two like fractions:
105/140 + 28/140 = 105 + 28/140 = 133/140 - 133/140 simplified gives 19/20
- So, 21/28 + 4/20 = 19/20
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