Add 15/21 and 42/45
15/21 + 42/45 is 173/105.
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,
42/45 = 42 × 7/45 × 7 = 294/315 - Add the two like fractions:
225/315 + 294/315 = 225 + 294/315 = 519/315 - 519/315 simplified gives 173/105
- So, 15/21 + 42/45 = 173/105
In mixed form: 168/105
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