Add 54/72 and 4/21
54/72 + 4/21 is 79/84.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 21 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 72 × 7 = 504,
54/72 = 54 × 7/72 × 7 = 378/504 - Likewise, for the 2nd fraction, since 21 × 24 = 504,
4/21 = 4 × 24/21 × 24 = 96/504 - Add the two like fractions:
378/504 + 96/504 = 378 + 96/504 = 474/504 - 474/504 simplified gives 79/84
- So, 54/72 + 4/21 = 79/84
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