Add 21/45 and 12/35
21/45 + 12/35 is 17/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 35 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 45 × 7 = 315,
21/45 = 21 × 7/45 × 7 = 147/315 - Likewise, for the 2nd fraction, since 35 × 9 = 315,
12/35 = 12 × 9/35 × 9 = 108/315 - Add the two like fractions:
147/315 + 108/315 = 147 + 108/315 = 255/315 - 255/315 simplified gives 17/21
- So, 21/45 + 12/35 = 17/21
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