Add 72/21 and 18/70
1st number: 3 9/21, 2nd number: 18/70
72/21 + 18/70 is 129/35.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 70 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 70 × 3 = 210,
18/70 = 18 × 3/70 × 3 = 54/210 - Add the two like fractions:
720/210 + 54/210 = 720 + 54/210 = 774/210 - 774/210 simplified gives 129/35
- So, 72/21 + 18/70 = 129/35
In mixed form: 324/35
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