Add 72/21 and 63/20
1st number: 3 9/21, 2nd number: 3 3/20
72/21 + 63/20 is 921/140.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 20 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 21 × 20 = 420,
72/21 = 72 × 20/21 × 20 = 1440/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
63/20 = 63 × 21/20 × 21 = 1323/420 - Add the two like fractions:
1440/420 + 1323/420 = 1440 + 1323/420 = 2763/420 - 2763/420 simplified gives 921/140
- So, 72/21 + 63/20 = 921/140
In mixed form: 681/140
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