Add 21/28 and 9/30
21/28 + 9/30 is 21/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 30 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 28 × 15 = 420,
21/28 = 21 × 15/28 × 15 = 315/420 - Likewise, for the 2nd fraction, since 30 × 14 = 420,
9/30 = 9 × 14/30 × 14 = 126/420 - Add the two like fractions:
315/420 + 126/420 = 315 + 126/420 = 441/420 - 441/420 simplified gives 21/20
- So, 21/28 + 9/30 = 21/20
In mixed form: 11/20
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