Add 28/21 and 21/25
1st number: 1 7/21, 2nd number: 21/25
28/21 + 21/25 is 163/75.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 25 is 525
Next, find the equivalent fraction of both fractional numbers with denominator 525 - For the 1st fraction, since 21 × 25 = 525,
28/21 = 28 × 25/21 × 25 = 700/525 - Likewise, for the 2nd fraction, since 25 × 21 = 525,
21/25 = 21 × 21/25 × 21 = 441/525 - Add the two like fractions:
700/525 + 441/525 = 700 + 441/525 = 1141/525 - 1141/525 simplified gives 163/75
- So, 28/21 + 21/25 = 163/75
In mixed form: 213/75
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