Add 20/21 and 15/42
20/21 + 15/42 is 55/42.
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,
15/42 = 15 × 1/42 × 1 = 15/42 - Add the two like fractions:
40/42 + 15/42 = 40 + 15/42 = 55/42 - So, 20/21 + 15/42 = 55/42
In mixed form: 113/42
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