Add 20/30 and 1/21
20/30 + 1/21 is 5/7.
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,
1/21 = 1 × 10/21 × 10 = 10/210 - Add the two like fractions:
140/210 + 10/210 = 140 + 10/210 = 150/210 - 150/210 simplified gives 5/7
- So, 20/30 + 1/21 = 5/7
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