Add 72/21 and 12/70
1st number: 3 9/21, 2nd number: 12/70
72/21 + 12/70 is 18/5.
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,
12/70 = 12 × 3/70 × 3 = 36/210 - Add the two like fractions:
720/210 + 36/210 = 720 + 36/210 = 756/210 - 756/210 simplified gives 18/5
- So, 72/21 + 12/70 = 18/5
In mixed form: 33/5
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