Add 21/63 and 42/45
21/63 + 42/45 is 19/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 63 and 45 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 63 × 5 = 315,
21/63 = 21 × 5/63 × 5 = 105/315 - Likewise, for the 2nd fraction, since 45 × 7 = 315,
42/45 = 42 × 7/45 × 7 = 294/315 - Add the two like fractions:
105/315 + 294/315 = 105 + 294/315 = 399/315 - 399/315 simplified gives 19/15
- So, 21/63 + 42/45 = 19/15
In mixed form: 14/15
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