Add 21/90 and 30/80
21/90 + 30/80 is 73/120.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 80 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 90 × 8 = 720,
21/90 = 21 × 8/90 × 8 = 168/720 - Likewise, for the 2nd fraction, since 80 × 9 = 720,
30/80 = 30 × 9/80 × 9 = 270/720 - Add the two like fractions:
168/720 + 270/720 = 168 + 270/720 = 438/720 - 438/720 simplified gives 73/120
- So, 21/90 + 30/80 = 73/120
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