Add 3/21 and 4/7
3/21 + 4/7 is 5/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 7 is 21
Next, find the equivalent fraction of both fractional numbers with denominator 21 - For the 1st fraction, since 21 × 1 = 21,
3/21 = 3 × 1/21 × 1 = 3/21 - Likewise, for the 2nd fraction, since 7 × 3 = 21,
4/7 = 4 × 3/7 × 3 = 12/21 - Add the two like fractions:
3/21 + 12/21 = 3 + 12/21 = 15/21 - 15/21 simplified gives 5/7
- So, 3/21 + 4/7 = 5/7
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