Add 20/28 and 21/72
20/28 + 21/72 is 169/168.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 28 × 18 = 504,
20/28 = 20 × 18/28 × 18 = 360/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
21/72 = 21 × 7/72 × 7 = 147/504 - Add the two like fractions:
360/504 + 147/504 = 360 + 147/504 = 507/504 - 507/504 simplified gives 169/168
- So, 20/28 + 21/72 = 169/168
In mixed form: 11/168
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