Add 42/20 and 72/81
1st number: 2 2/20, 2nd number: 72/81
42/20 + 72/81 is 269/90.
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,
42/20 = 42 × 81/20 × 81 = 3402/1620 - Likewise, for the 2nd fraction, since 81 × 20 = 1620,
72/81 = 72 × 20/81 × 20 = 1440/1620 - Add the two like fractions:
3402/1620 + 1440/1620 = 3402 + 1440/1620 = 4842/1620 - 4842/1620 simplified gives 269/90
- So, 42/20 + 72/81 = 269/90
In mixed form: 289/90
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