Add 21/27 and 28/40
21/27 + 28/40 is 133/90.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 27 and 40 is 1080
Next, find the equivalent fraction of both fractional numbers with denominator 1080 - For the 1st fraction, since 27 × 40 = 1080,
21/27 = 21 × 40/27 × 40 = 840/1080 - Likewise, for the 2nd fraction, since 40 × 27 = 1080,
28/40 = 28 × 27/40 × 27 = 756/1080 - Add the two like fractions:
840/1080 + 756/1080 = 840 + 756/1080 = 1596/1080 - 1596/1080 simplified gives 133/90
- So, 21/27 + 28/40 = 133/90
In mixed form: 143/90
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