Add 1/21 and 28/42
1/21 + 28/42 is 5/7.
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,
1/21 = 1 × 2/21 × 2 = 2/42 - Likewise, for the 2nd fraction, since 42 × 1 = 42,
28/42 = 28 × 1/42 × 1 = 28/42 - Add the two like fractions:
2/42 + 28/42 = 2 + 28/42 = 30/42 - 30/42 simplified gives 5/7
- So, 1/21 + 28/42 = 5/7
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