Add 72/21 and 75/30
1st number: 3 9/21, 2nd number: 2 15/30
72/21 + 75/30 is 83/14.
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,
72/21 = 72 × 10/21 × 10 = 720/210 - Likewise, for the 2nd fraction, since 30 × 7 = 210,
75/30 = 75 × 7/30 × 7 = 525/210 - Add the two like fractions:
720/210 + 525/210 = 720 + 525/210 = 1245/210 - 1245/210 simplified gives 83/14
- So, 72/21 + 75/30 = 83/14
In mixed form: 513/14
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