Add 4/21 and 81/72
1st number: 4/21, 2nd number: 1 9/72
4/21 + 81/72 is 221/168.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 21 × 24 = 504,
4/21 = 4 × 24/21 × 24 = 96/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
81/72 = 81 × 7/72 × 7 = 567/504 - Add the two like fractions:
96/504 + 567/504 = 96 + 567/504 = 663/504 - 663/504 simplified gives 221/168
- So, 4/21 + 81/72 = 221/168
In mixed form: 153/168
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