Add 81/8 and 42/20
1st number: 10 1/8, 2nd number: 2 2/20
81/8 + 42/20 is 489/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 20 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 8 × 5 = 40,
81/8 = 81 × 5/8 × 5 = 405/40 - Likewise, for the 2nd fraction, since 20 × 2 = 40,
42/20 = 42 × 2/20 × 2 = 84/40 - Add the two like fractions:
405/40 + 84/40 = 405 + 84/40 = 489/40 - So, 81/8 + 42/20 = 489/40
In mixed form: 129/40
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