Add 12/21 and 28/30
12/21 + 28/30 is 158/105.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 30 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 21 × 10 = 210,
12/21 = 12 × 10/21 × 10 = 120/210 - Likewise, for the 2nd fraction, since 30 × 7 = 210,
28/30 = 28 × 7/30 × 7 = 196/210 - Add the two like fractions:
120/210 + 196/210 = 120 + 196/210 = 316/210 - 316/210 simplified gives 158/105
- So, 12/21 + 28/30 = 158/105
In mixed form: 153/105
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