Add 20/42 and 1/21
20/42 + 1/21 is 11/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 21 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 42 × 1 = 42,
20/42 = 20 × 1/42 × 1 = 20/42 - Likewise, for the 2nd fraction, since 21 × 2 = 42,
1/21 = 1 × 2/21 × 2 = 2/42 - Add the two like fractions:
20/42 + 2/42 = 20 + 2/42 = 22/42 - 22/42 simplified gives 11/21
- So, 20/42 + 1/21 = 11/21
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