Add 72/21 and 20/10
1st number: 3 9/21, 2nd number: 2 0/10
72/21 + 20/10 is 38/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 10 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 10 × 21 = 210,
20/10 = 20 × 21/10 × 21 = 420/210 - Add the two like fractions:
720/210 + 420/210 = 720 + 420/210 = 1140/210 - 1140/210 simplified gives 38/7
- So, 72/21 + 20/10 = 38/7
In mixed form: 53/7
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