Add 18/20 and 21/27
18/20 + 21/27 is 151/90.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 27 is 540
Next, find the equivalent fraction of both fractional numbers with denominator 540 - For the 1st fraction, since 20 × 27 = 540,
18/20 = 18 × 27/20 × 27 = 486/540 - Likewise, for the 2nd fraction, since 27 × 20 = 540,
21/27 = 21 × 20/27 × 20 = 420/540 - Add the two like fractions:
486/540 + 420/540 = 486 + 420/540 = 906/540 - 906/540 simplified gives 151/90
- So, 18/20 + 21/27 = 151/90
In mixed form: 161/90
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