Add 21/72 and 84/20
1st number: 21/72, 2nd number: 4 4/20
21/72 + 84/20 is 539/120.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 20 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 72 × 5 = 360,
21/72 = 21 × 5/72 × 5 = 105/360 - Likewise, for the 2nd fraction, since 20 × 18 = 360,
84/20 = 84 × 18/20 × 18 = 1512/360 - Add the two like fractions:
105/360 + 1512/360 = 105 + 1512/360 = 1617/360 - 1617/360 simplified gives 539/120
- So, 21/72 + 84/20 = 539/120
In mixed form: 459/120
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