Add 72/20 and 30/18
1st number: 3 12/20, 2nd number: 1 12/18
72/20 + 30/18 is 79/15.
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,
30/18 = 30 × 10/18 × 10 = 300/180 - Add the two like fractions:
648/180 + 300/180 = 648 + 300/180 = 948/180 - 948/180 simplified gives 79/15
- So, 72/20 + 30/18 = 79/15
In mixed form: 54/15
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