Add 15/45 and 15/21
15/45 + 15/21 is 22/21.
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,
15/45 = 15 × 7/45 × 7 = 105/315 - Likewise, for the 2nd fraction, since 21 × 15 = 315,
15/21 = 15 × 15/21 × 15 = 225/315 - Add the two like fractions:
105/315 + 225/315 = 105 + 225/315 = 330/315 - 330/315 simplified gives 22/21
- So, 15/45 + 15/21 = 22/21
In mixed form: 11/21
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