Add 12/42 and 18/20
12/42 + 18/20 is 83/70.
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,
12/42 = 12 × 10/42 × 10 = 120/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
18/20 = 18 × 21/20 × 21 = 378/420 - Add the two like fractions:
120/420 + 378/420 = 120 + 378/420 = 498/420 - 498/420 simplified gives 83/70
- So, 12/42 + 18/20 = 83/70
In mixed form: 113/70
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