Add 1/20 and 28/21
1st number: 1/20, 2nd number: 1 7/21
1/20 + 28/21 is 83/60.
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,
1/20 = 1 × 21/20 × 21 = 21/420 - Likewise, for the 2nd fraction, since 21 × 20 = 420,
28/21 = 28 × 20/21 × 20 = 560/420 - Add the two like fractions:
21/420 + 560/420 = 21 + 560/420 = 581/420 - 581/420 simplified gives 83/60
- So, 1/20 + 28/21 = 83/60
In mixed form: 123/60
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