Add 15/21 and 30/45
15/21 + 30/45 is 29/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 45 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 21 × 15 = 315,
15/21 = 15 × 15/21 × 15 = 225/315 - Likewise, for the 2nd fraction, since 45 × 7 = 315,
30/45 = 30 × 7/45 × 7 = 210/315 - Add the two like fractions:
225/315 + 210/315 = 225 + 210/315 = 435/315 - 435/315 simplified gives 29/21
- So, 15/21 + 30/45 = 29/21
In mixed form: 18/21
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