Add 7/21 and 2/5
7/21 + 2/5 is 11/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 5 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 21 × 5 = 105,
7/21 = 7 × 5/21 × 5 = 35/105 - Likewise, for the 2nd fraction, since 5 × 21 = 105,
2/5 = 2 × 21/5 × 21 = 42/105 - Add the two like fractions:
35/105 + 42/105 = 35 + 42/105 = 77/105 - 77/105 simplified gives 11/15
- So, 7/21 + 2/5 = 11/15
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