Add 20/30 and 28/21
1st number: 20/30, 2nd number: 1 7/21
20/30 + 28/21 is 2/1.
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,
20/30 = 20 × 7/30 × 7 = 140/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
28/21 = 28 × 10/21 × 10 = 280/210 - Add the two like fractions:
140/210 + 280/210 = 140 + 280/210 = 420/210 - 420/210 simplified gives 2/1
- So, 20/30 + 28/21 = 2/1
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