Add 15/21 and 20/30
15/21 + 20/30 is 29/21.
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,
15/21 = 15 × 10/21 × 10 = 150/210 - Likewise, for the 2nd fraction, since 30 × 7 = 210,
20/30 = 20 × 7/30 × 7 = 140/210 - Add the two like fractions:
150/210 + 140/210 = 150 + 140/210 = 290/210 - 290/210 simplified gives 29/21
- So, 15/21 + 20/30 = 29/21
In mixed form: 18/21
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