Add 21/80 and 4/90
21/80 + 4/90 is 221/720.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 90 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 80 × 9 = 720,
21/80 = 21 × 9/80 × 9 = 189/720 - Likewise, for the 2nd fraction, since 90 × 8 = 720,
4/90 = 4 × 8/90 × 8 = 32/720 - Add the two like fractions:
189/720 + 32/720 = 189 + 32/720 = 221/720 - So, 21/80 + 4/90 = 221/720
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