Add 15/25 and 42/21
1st number: 15/25, 2nd number: 2 0/21
15/25 + 42/21 is 13/5.
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,
42/21 = 42 × 25/21 × 25 = 1050/525 - Add the two like fractions:
315/525 + 1050/525 = 315 + 1050/525 = 1365/525 - 1365/525 simplified gives 13/5
- So, 15/25 + 42/21 = 13/5
In mixed form: 23/5
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