Add 81/42 and 8/20
1st number: 1 39/42, 2nd number: 8/20
81/42 + 8/20 is 163/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 20 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 42 × 10 = 420,
81/42 = 81 × 10/42 × 10 = 810/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
8/20 = 8 × 21/20 × 21 = 168/420 - Add the two like fractions:
810/420 + 168/420 = 810 + 168/420 = 978/420 - 978/420 simplified gives 163/70
- So, 81/42 + 8/20 = 163/70
In mixed form: 223/70
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