Add 20/25 and 28/21
1st number: 20/25, 2nd number: 1 7/21
20/25 + 28/21 is 32/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 25 and 21 is 525
Next, find the equivalent fraction of both fractional numbers with denominator 525 - For the 1st fraction, since 25 × 21 = 525,
20/25 = 20 × 21/25 × 21 = 420/525 - Likewise, for the 2nd fraction, since 21 × 25 = 525,
28/21 = 28 × 25/21 × 25 = 700/525 - Add the two like fractions:
420/525 + 700/525 = 420 + 700/525 = 1120/525 - 1120/525 simplified gives 32/15
- So, 20/25 + 28/21 = 32/15
In mixed form: 22/15
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