Add 15/21 and 3/30
15/21 + 3/30 is 57/70.
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,
3/30 = 3 × 7/30 × 7 = 21/210 - Add the two like fractions:
150/210 + 21/210 = 150 + 21/210 = 171/210 - 171/210 simplified gives 57/70
- So, 15/21 + 3/30 = 57/70
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