Add 21/63 and 42/72
21/63 + 42/72 is 11/12.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 63 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 63 × 8 = 504,
21/63 = 21 × 8/63 × 8 = 168/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
42/72 = 42 × 7/72 × 7 = 294/504 - Add the two like fractions:
168/504 + 294/504 = 168 + 294/504 = 462/504 - 462/504 simplified gives 11/12
- So, 21/63 + 42/72 = 11/12
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