Add 81/21 and 30/40
1st number: 3 18/21, 2nd number: 30/40
81/21 + 30/40 is 129/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 21 × 40 = 840,
81/21 = 81 × 40/21 × 40 = 3240/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
30/40 = 30 × 21/40 × 21 = 630/840 - Add the two like fractions:
3240/840 + 630/840 = 3240 + 630/840 = 3870/840 - 3870/840 simplified gives 129/28
- So, 81/21 + 30/40 = 129/28
In mixed form: 417/28
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