Add 30/28 and 72/21
1st number: 1 2/28, 2nd number: 3 9/21
30/28 + 72/21 is 9/2.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 28 × 3 = 84,
30/28 = 30 × 3/28 × 3 = 90/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
72/21 = 72 × 4/21 × 4 = 288/84 - Add the two like fractions:
90/84 + 288/84 = 90 + 288/84 = 378/84 - 378/84 simplified gives 9/2
- So, 30/28 + 72/21 = 9/2
In mixed form: 41/2
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