Add 20/70 and 81/42
1st number: 20/70, 2nd number: 1 39/42
20/70 + 81/42 is 31/14.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 42 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 70 × 3 = 210,
20/70 = 20 × 3/70 × 3 = 60/210 - Likewise, for the 2nd fraction, since 42 × 5 = 210,
81/42 = 81 × 5/42 × 5 = 405/210 - Add the two like fractions:
60/210 + 405/210 = 60 + 405/210 = 465/210 - 465/210 simplified gives 31/14
- So, 20/70 + 81/42 = 31/14
In mixed form: 23/14
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