Add 81/7 and 20/40
1st number: 11 4/7, 2nd number: 20/40
81/7 + 20/40 is 169/14.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 40 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 7 × 40 = 280,
81/7 = 81 × 40/7 × 40 = 3240/280 - Likewise, for the 2nd fraction, since 40 × 7 = 280,
20/40 = 20 × 7/40 × 7 = 140/280 - Add the two like fractions:
3240/280 + 140/280 = 3240 + 140/280 = 3380/280 - 3380/280 simplified gives 169/14
- So, 81/7 + 20/40 = 169/14
In mixed form: 121/14
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