Add 72/20 and 90/18
1st number: 3 12/20, 2nd number: 5 0/18
72/20 + 90/18 is 43/5.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 18 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 20 × 9 = 180,
72/20 = 72 × 9/20 × 9 = 648/180 - Likewise, for the 2nd fraction, since 18 × 10 = 180,
90/18 = 90 × 10/18 × 10 = 900/180 - Add the two like fractions:
648/180 + 900/180 = 648 + 900/180 = 1548/180 - 1548/180 simplified gives 43/5
- So, 72/20 + 90/18 = 43/5
In mixed form: 83/5
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