Add 9/42 and 12/20
9/42 + 12/20 is 57/70.
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,
9/42 = 9 × 10/42 × 10 = 90/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
12/20 = 12 × 21/20 × 21 = 252/420 - Add the two like fractions:
90/420 + 252/420 = 90 + 252/420 = 342/420 - 342/420 simplified gives 57/70
- So, 9/42 + 12/20 = 57/70
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