Add 21/20 and 12/72
1st number: 1 1/20, 2nd number: 12/72
21/20 + 12/72 is 73/60.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 72 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 20 × 18 = 360,
21/20 = 21 × 18/20 × 18 = 378/360 - Likewise, for the 2nd fraction, since 72 × 5 = 360,
12/72 = 12 × 5/72 × 5 = 60/360 - Add the two like fractions:
378/360 + 60/360 = 378 + 60/360 = 438/360 - 438/360 simplified gives 73/60
- So, 21/20 + 12/72 = 73/60
In mixed form: 113/60
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