Add 21/28 and 20/27
21/28 + 20/27 is 161/108.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 27 is 756
Next, find the equivalent fraction of both fractional numbers with denominator 756 - For the 1st fraction, since 28 × 27 = 756,
21/28 = 21 × 27/28 × 27 = 567/756 - Likewise, for the 2nd fraction, since 27 × 28 = 756,
20/27 = 20 × 28/27 × 28 = 560/756 - Add the two like fractions:
567/756 + 560/756 = 567 + 560/756 = 1127/756 - 1127/756 simplified gives 161/108
- So, 21/28 + 20/27 = 161/108
In mixed form: 153/108
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