Add 81/21 and 40/5
1st number: 3 18/21, 2nd number: 8 0/5
81/21 + 40/5 is 83/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 5 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 21 × 5 = 105,
81/21 = 81 × 5/21 × 5 = 405/105 - Likewise, for the 2nd fraction, since 5 × 21 = 105,
40/5 = 40 × 21/5 × 21 = 840/105 - Add the two like fractions:
405/105 + 840/105 = 405 + 840/105 = 1245/105 - 1245/105 simplified gives 83/7
- So, 81/21 + 40/5 = 83/7
In mixed form: 116/7
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