Add 15/84 and 21/30
15/84 + 21/30 is 123/140.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 30 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 84 × 5 = 420,
15/84 = 15 × 5/84 × 5 = 75/420 - Likewise, for the 2nd fraction, since 30 × 14 = 420,
21/30 = 21 × 14/30 × 14 = 294/420 - Add the two like fractions:
75/420 + 294/420 = 75 + 294/420 = 369/420 - 369/420 simplified gives 123/140
- So, 15/84 + 21/30 = 123/140
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