Add 72/30 and 70/21
1st number: 2 12/30, 2nd number: 3 7/21
72/30 + 70/21 is 86/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 21 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 30 × 7 = 210,
72/30 = 72 × 7/30 × 7 = 504/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
70/21 = 70 × 10/21 × 10 = 700/210 - Add the two like fractions:
504/210 + 700/210 = 504 + 700/210 = 1204/210 - 1204/210 simplified gives 86/15
- So, 72/30 + 70/21 = 86/15
In mixed form: 511/15
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