Add 90/60 and 21/28
1st number: 1 30/60, 2nd number: 21/28
90/60 + 21/28 is 9/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 60 and 28 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 60 × 7 = 420,
90/60 = 90 × 7/60 × 7 = 630/420 - Likewise, for the 2nd fraction, since 28 × 15 = 420,
21/28 = 21 × 15/28 × 15 = 315/420 - Add the two like fractions:
630/420 + 315/420 = 630 + 315/420 = 945/420 - 945/420 simplified gives 9/4
- So, 90/60 + 21/28 = 9/4
In mixed form: 21/4
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