Add 28/20 and 21/42
1st number: 1 8/20, 2nd number: 21/42
28/20 + 21/42 is 19/10.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 42 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 20 × 21 = 420,
28/20 = 28 × 21/20 × 21 = 588/420 - Likewise, for the 2nd fraction, since 42 × 10 = 420,
21/42 = 21 × 10/42 × 10 = 210/420 - Add the two like fractions:
588/420 + 210/420 = 588 + 210/420 = 798/420 - 798/420 simplified gives 19/10
- So, 28/20 + 21/42 = 19/10
In mixed form: 19/10
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