Add 21/35 and 12/45
21/35 + 12/45 is 13/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 35 and 45 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 35 × 9 = 315,
21/35 = 21 × 9/35 × 9 = 189/315 - Likewise, for the 2nd fraction, since 45 × 7 = 315,
12/45 = 12 × 7/45 × 7 = 84/315 - Add the two like fractions:
189/315 + 84/315 = 189 + 84/315 = 273/315 - 273/315 simplified gives 13/15
- So, 21/35 + 12/45 = 13/15
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