Add 15/25 and 20/21
15/25 + 20/21 is 163/105.
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,
15/25 = 15 × 21/25 × 21 = 315/525 - Likewise, for the 2nd fraction, since 21 × 25 = 525,
20/21 = 20 × 25/21 × 25 = 500/525 - Add the two like fractions:
315/525 + 500/525 = 315 + 500/525 = 815/525 - 815/525 simplified gives 163/105
- So, 15/25 + 20/21 = 163/105
In mixed form: 158/105
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