Add 21/45 and 42/63
21/45 + 42/63 is 17/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 63 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 45 × 7 = 315,
21/45 = 21 × 7/45 × 7 = 147/315 - Likewise, for the 2nd fraction, since 63 × 5 = 315,
42/63 = 42 × 5/63 × 5 = 210/315 - Add the two like fractions:
147/315 + 210/315 = 147 + 210/315 = 357/315 - 357/315 simplified gives 17/15
- So, 21/45 + 42/63 = 17/15
In mixed form: 12/15
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