Add 72/90 and 30/80
72/90 + 30/80 is 47/40.
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,
30/80 = 30 × 9/80 × 9 = 270/720 - Add the two like fractions:
576/720 + 270/720 = 576 + 270/720 = 846/720 - 846/720 simplified gives 47/40
- So, 72/90 + 30/80 = 47/40
In mixed form: 17/40
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