Add 21/30 and 84/72
1st number: 21/30, 2nd number: 1 12/72
21/30 + 84/72 is 28/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 72 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 30 × 12 = 360,
21/30 = 21 × 12/30 × 12 = 252/360 - Likewise, for the 2nd fraction, since 72 × 5 = 360,
84/72 = 84 × 5/72 × 5 = 420/360 - Add the two like fractions:
252/360 + 420/360 = 252 + 420/360 = 672/360 - 672/360 simplified gives 28/15
- So, 21/30 + 84/72 = 28/15
In mixed form: 113/15
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