Add 28/21 and 72/30
1st number: 1 7/21, 2nd number: 2 12/30
28/21 + 72/30 is 56/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 30 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 21 × 10 = 210,
28/21 = 28 × 10/21 × 10 = 280/210 - Likewise, for the 2nd fraction, since 30 × 7 = 210,
72/30 = 72 × 7/30 × 7 = 504/210 - Add the two like fractions:
280/210 + 504/210 = 280 + 504/210 = 784/210 - 784/210 simplified gives 56/15
- So, 28/21 + 72/30 = 56/15
In mixed form: 311/15
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