Add 9/42 and 12/40
9/42 + 12/40 is 18/35.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 42 × 20 = 840,
9/42 = 9 × 20/42 × 20 = 180/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
12/40 = 12 × 21/40 × 21 = 252/840 - Add the two like fractions:
180/840 + 252/840 = 180 + 252/840 = 432/840 - 432/840 simplified gives 18/35
- So, 9/42 + 12/40 = 18/35
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