Add 28/72 and 18/21
28/72 + 18/21 is 157/126.
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,
28/72 = 28 × 7/72 × 7 = 196/504 - Likewise, for the 2nd fraction, since 21 × 24 = 504,
18/21 = 18 × 24/21 × 24 = 432/504 - Add the two like fractions:
196/504 + 432/504 = 196 + 432/504 = 628/504 - 628/504 simplified gives 157/126
- So, 28/72 + 18/21 = 157/126
In mixed form: 131/126
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