Add 90/30 and 21/28
1st number: 3 0/30, 2nd number: 21/28
90/30 + 21/28 is 15/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 28 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 30 × 14 = 420,
90/30 = 90 × 14/30 × 14 = 1260/420 - Likewise, for the 2nd fraction, since 28 × 15 = 420,
21/28 = 21 × 15/28 × 15 = 315/420 - Add the two like fractions:
1260/420 + 315/420 = 1260 + 315/420 = 1575/420 - 1575/420 simplified gives 15/4
- So, 90/30 + 21/28 = 15/4
In mixed form: 33/4
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