Add 21/42 and 20/30
21/42 + 20/30 is 7/6.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 30 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 42 × 5 = 210,
21/42 = 21 × 5/42 × 5 = 105/210 - Likewise, for the 2nd fraction, since 30 × 7 = 210,
20/30 = 20 × 7/30 × 7 = 140/210 - Add the two like fractions:
105/210 + 140/210 = 105 + 140/210 = 245/210 - 245/210 simplified gives 7/6
- So, 21/42 + 20/30 = 7/6
In mixed form: 11/6
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