Add 72/20 and 40/81
1st number: 3 12/20, 2nd number: 40/81
72/20 + 40/81 is 1658/405.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 81 is 1620
Next, find the equivalent fraction of both fractional numbers with denominator 1620 - For the 1st fraction, since 20 × 81 = 1620,
72/20 = 72 × 81/20 × 81 = 5832/1620 - Likewise, for the 2nd fraction, since 81 × 20 = 1620,
40/81 = 40 × 20/81 × 20 = 800/1620 - Add the two like fractions:
5832/1620 + 800/1620 = 5832 + 800/1620 = 6632/1620 - 6632/1620 simplified gives 1658/405
- So, 72/20 + 40/81 = 1658/405
In mixed form: 438/405
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