Add 4/21 and 7/15
4/21 + 7/15 is 23/35.
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,
4/21 = 4 × 5/21 × 5 = 20/105 - Likewise, for the 2nd fraction, since 15 × 7 = 105,
7/15 = 7 × 7/15 × 7 = 49/105 - Add the two like fractions:
20/105 + 49/105 = 20 + 49/105 = 69/105 - 69/105 simplified gives 23/35
- So, 4/21 + 7/15 = 23/35
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