Add 81/21 and 70/72
1st number: 3 18/21, 2nd number: 70/72
81/21 + 70/72 is 1217/252.
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,
81/21 = 81 × 24/21 × 24 = 1944/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
70/72 = 70 × 7/72 × 7 = 490/504 - Add the two like fractions:
1944/504 + 490/504 = 1944 + 490/504 = 2434/504 - 2434/504 simplified gives 1217/252
- So, 81/21 + 70/72 = 1217/252
In mixed form: 4209/252
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