Add 3/21 and 12/15
3/21 + 12/15 is 33/35.
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,
3/21 = 3 × 5/21 × 5 = 15/105 - Likewise, for the 2nd fraction, since 15 × 7 = 105,
12/15 = 12 × 7/15 × 7 = 84/105 - Add the two like fractions:
15/105 + 84/105 = 15 + 84/105 = 99/105 - 99/105 simplified gives 33/35
- So, 3/21 + 12/15 = 33/35
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