Add 81/72 and 2/21
1st number: 1 9/72, 2nd number: 2/21
81/72 + 2/21 is 205/168.
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,
81/72 = 81 × 7/72 × 7 = 567/504 - Likewise, for the 2nd fraction, since 21 × 24 = 504,
2/21 = 2 × 24/21 × 24 = 48/504 - Add the two like fractions:
567/504 + 48/504 = 567 + 48/504 = 615/504 - 615/504 simplified gives 205/168
- So, 81/72 + 2/21 = 205/168
In mixed form: 137/168
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