Add 1/21 and 1/15
1/21 + 1/15 is 4/35.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 15 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 21 × 5 = 105,
1/21 = 1 × 5/21 × 5 = 5/105 - Likewise, for the 2nd fraction, since 15 × 7 = 105,
1/15 = 1 × 7/15 × 7 = 7/105 - Add the two like fractions:
5/105 + 7/105 = 5 + 7/105 = 12/105 - 12/105 simplified gives 4/35
- So, 1/21 + 1/15 = 4/35
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