Add 15/45 and 18/21
15/45 + 18/21 is 25/21.
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,
18/21 = 18 × 15/21 × 15 = 270/315 - Add the two like fractions:
105/315 + 270/315 = 105 + 270/315 = 375/315 - 375/315 simplified gives 25/21
- So, 15/45 + 18/21 = 25/21
In mixed form: 14/21
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