Add 20/80 and 21/90
20/80 + 21/90 is 29/60.
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,
20/80 = 20 × 9/80 × 9 = 180/720 - Likewise, for the 2nd fraction, since 90 × 8 = 720,
21/90 = 21 × 8/90 × 8 = 168/720 - Add the two like fractions:
180/720 + 168/720 = 180 + 168/720 = 348/720 - 348/720 simplified gives 29/60
- So, 20/80 + 21/90 = 29/60
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