Add 27/30 and 18/21
27/30 + 18/21 is 123/70.
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,
27/30 = 27 × 7/30 × 7 = 189/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
18/21 = 18 × 10/21 × 10 = 180/210 - Add the two like fractions:
189/210 + 180/210 = 189 + 180/210 = 369/210 - 369/210 simplified gives 123/70
- So, 27/30 + 18/21 = 123/70
In mixed form: 153/70
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