Add 70/72 and 21/28
70/72 + 21/28 is 31/18.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 28 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 72 × 7 = 504,
70/72 = 70 × 7/72 × 7 = 490/504 - Likewise, for the 2nd fraction, since 28 × 18 = 504,
21/28 = 21 × 18/28 × 18 = 378/504 - Add the two like fractions:
490/504 + 378/504 = 490 + 378/504 = 868/504 - 868/504 simplified gives 31/18
- So, 70/72 + 21/28 = 31/18
In mixed form: 113/18
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