Add 3/20 and 81/21
1st number: 3/20, 2nd number: 3 18/21
3/20 + 81/21 is 561/140.
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,
81/21 = 81 × 20/21 × 20 = 1620/420 - Add the two like fractions:
63/420 + 1620/420 = 63 + 1620/420 = 1683/420 - 1683/420 simplified gives 561/140
- So, 3/20 + 81/21 = 561/140
In mixed form: 41/140
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