Add 20/28 and 42/72
20/28 + 42/72 is 109/84.
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,
42/72 = 42 × 7/72 × 7 = 294/504 - Add the two like fractions:
360/504 + 294/504 = 360 + 294/504 = 654/504 - 654/504 simplified gives 109/84
- So, 20/28 + 42/72 = 109/84
In mixed form: 125/84
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