Add 21/90 and 28/45
21/90 + 28/45 is 77/90.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 45 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 90 × 1 = 90,
21/90 = 21 × 1/90 × 1 = 21/90 - Likewise, for the 2nd fraction, since 45 × 2 = 90,
28/45 = 28 × 2/45 × 2 = 56/90 - Add the two like fractions:
21/90 + 56/90 = 21 + 56/90 = 77/90 - So, 21/90 + 28/45 = 77/90
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