Add 21/18 and 72/20
1st number: 1 3/18, 2nd number: 3 12/20
21/18 + 72/20 is 143/30.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 20 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 18 × 10 = 180,
21/18 = 21 × 10/18 × 10 = 210/180 - Likewise, for the 2nd fraction, since 20 × 9 = 180,
72/20 = 72 × 9/20 × 9 = 648/180 - Add the two like fractions:
210/180 + 648/180 = 210 + 648/180 = 858/180 - 858/180 simplified gives 143/30
- So, 21/18 + 72/20 = 143/30
In mixed form: 423/30
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