Add 15/25 and 21/28
15/25 + 21/28 is 27/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 25 and 28 is 700
Next, find the equivalent fraction of both fractional numbers with denominator 700 - For the 1st fraction, since 25 × 28 = 700,
15/25 = 15 × 28/25 × 28 = 420/700 - Likewise, for the 2nd fraction, since 28 × 25 = 700,
21/28 = 21 × 25/28 × 25 = 525/700 - Add the two like fractions:
420/700 + 525/700 = 420 + 525/700 = 945/700 - 945/700 simplified gives 27/20
- So, 15/25 + 21/28 = 27/20
In mixed form: 17/20
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