Add 63/5 and 81/21
1st number: 12 3/5, 2nd number: 3 18/21
63/5 + 81/21 is 576/35.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 5 × 21 = 105,
63/5 = 63 × 21/5 × 21 = 1323/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
81/21 = 81 × 5/21 × 5 = 405/105 - Add the two like fractions:
1323/105 + 405/105 = 1323 + 405/105 = 1728/105 - 1728/105 simplified gives 576/35
- So, 63/5 + 81/21 = 576/35
In mixed form: 1616/35
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