Add 3/20 and 28/21
1st number: 3/20, 2nd number: 1 7/21
3/20 + 28/21 is 89/60.
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,
3/20 = 3 × 21/20 × 21 = 63/420 - Likewise, for the 2nd fraction, since 21 × 20 = 420,
28/21 = 28 × 20/21 × 20 = 560/420 - Add the two like fractions:
63/420 + 560/420 = 63 + 560/420 = 623/420 - 623/420 simplified gives 89/60
- So, 3/20 + 28/21 = 89/60
In mixed form: 129/60
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