Add 20/21 and 18/42
20/21 + 18/42 is 29/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 42 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 21 × 2 = 42,
20/21 = 20 × 2/21 × 2 = 40/42 - Likewise, for the 2nd fraction, since 42 × 1 = 42,
18/42 = 18 × 1/42 × 1 = 18/42 - Add the two like fractions:
40/42 + 18/42 = 40 + 18/42 = 58/42 - 58/42 simplified gives 29/21
- So, 20/21 + 18/42 = 29/21
In mixed form: 18/21
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