Add 15/30 and 5/21
15/30 + 5/21 is 31/42.
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,
5/21 = 5 × 10/21 × 10 = 50/210 - Add the two like fractions:
105/210 + 50/210 = 105 + 50/210 = 155/210 - 155/210 simplified gives 31/42
- So, 15/30 + 5/21 = 31/42
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