Add 12/45 and 5/21
12/45 + 5/21 is 53/105.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 21 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 45 × 7 = 315,
12/45 = 12 × 7/45 × 7 = 84/315 - Likewise, for the 2nd fraction, since 21 × 15 = 315,
5/21 = 5 × 15/21 × 15 = 75/315 - Add the two like fractions:
84/315 + 75/315 = 84 + 75/315 = 159/315 - 159/315 simplified gives 53/105
- So, 12/45 + 5/21 = 53/105
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