Add 20/45 and 72/80
20/45 + 72/80 is 121/90.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 80 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 45 × 16 = 720,
20/45 = 20 × 16/45 × 16 = 320/720 - Likewise, for the 2nd fraction, since 80 × 9 = 720,
72/80 = 72 × 9/80 × 9 = 648/720 - Add the two like fractions:
320/720 + 648/720 = 320 + 648/720 = 968/720 - 968/720 simplified gives 121/90
- So, 20/45 + 72/80 = 121/90
In mixed form: 131/90
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