Add 21/28 and 90/25
1st number: 21/28, 2nd number: 3 15/25
21/28 + 90/25 is 87/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 25 is 700
Next, find the equivalent fraction of both fractional numbers with denominator 700 - For the 1st fraction, since 28 × 25 = 700,
21/28 = 21 × 25/28 × 25 = 525/700 - Likewise, for the 2nd fraction, since 25 × 28 = 700,
90/25 = 90 × 28/25 × 28 = 2520/700 - Add the two like fractions:
525/700 + 2520/700 = 525 + 2520/700 = 3045/700 - 3045/700 simplified gives 87/20
- So, 21/28 + 90/25 = 87/20
In mixed form: 47/20
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