Add 25/45 and 72/21
1st number: 25/45, 2nd number: 3 9/21
25/45 + 72/21 is 251/63.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 21 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 45 × 7 = 315,
25/45 = 25 × 7/45 × 7 = 175/315 - Likewise, for the 2nd fraction, since 21 × 15 = 315,
72/21 = 72 × 15/21 × 15 = 1080/315 - Add the two like fractions:
175/315 + 1080/315 = 175 + 1080/315 = 1255/315 - 1255/315 simplified gives 251/63
- So, 25/45 + 72/21 = 251/63
In mixed form: 362/63
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