Add 15/30 and 12/21
15/30 + 12/21 is 15/14.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 21 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 30 × 7 = 210,
15/30 = 15 × 7/30 × 7 = 105/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
12/21 = 12 × 10/21 × 10 = 120/210 - Add the two like fractions:
105/210 + 120/210 = 105 + 120/210 = 225/210 - 225/210 simplified gives 15/14
- So, 15/30 + 12/21 = 15/14
In mixed form: 11/14
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