Add 72/90 and 20/80
72/90 + 20/80 is 21/20.
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,
72/90 = 72 × 8/90 × 8 = 576/720 - Likewise, for the 2nd fraction, since 80 × 9 = 720,
20/80 = 20 × 9/80 × 9 = 180/720 - Add the two like fractions:
576/720 + 180/720 = 576 + 180/720 = 756/720 - 756/720 simplified gives 21/20
- So, 72/90 + 20/80 = 21/20
In mixed form: 11/20
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