Add 28/20 and 42/21
1st number: 1 8/20, 2nd number: 2 0/21
28/20 + 42/21 is 17/5.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 21 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 21 × 20 = 420,
42/21 = 42 × 20/21 × 20 = 840/420 - Add the two like fractions:
588/420 + 840/420 = 588 + 840/420 = 1428/420 - 1428/420 simplified gives 17/5
- So, 28/20 + 42/21 = 17/5
In mixed form: 32/5
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