Add 15/25 and 21/8
1st number: 15/25, 2nd number: 2 5/8
15/25 + 21/8 is 129/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 25 and 8 is 200
Next, find the equivalent fraction of both fractional numbers with denominator 200 - For the 1st fraction, since 25 × 8 = 200,
15/25 = 15 × 8/25 × 8 = 120/200 - Likewise, for the 2nd fraction, since 8 × 25 = 200,
21/8 = 21 × 25/8 × 25 = 525/200 - Add the two like fractions:
120/200 + 525/200 = 120 + 525/200 = 645/200 - 645/200 simplified gives 129/40
- So, 15/25 + 21/8 = 129/40
In mixed form: 39/40
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