Add 21/84 and 90/75
1st number: 21/84, 2nd number: 1 15/75
21/84 + 90/75 is 29/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 75 is 2100
Next, find the equivalent fraction of both fractional numbers with denominator 2100 - For the 1st fraction, since 84 × 25 = 2100,
21/84 = 21 × 25/84 × 25 = 525/2100 - Likewise, for the 2nd fraction, since 75 × 28 = 2100,
90/75 = 90 × 28/75 × 28 = 2520/2100 - Add the two like fractions:
525/2100 + 2520/2100 = 525 + 2520/2100 = 3045/2100 - 3045/2100 simplified gives 29/20
- So, 21/84 + 90/75 = 29/20
In mixed form: 19/20
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