Add 20/40 and 9/42
20/40 + 9/42 is 5/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 42 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 40 × 21 = 840,
20/40 = 20 × 21/40 × 21 = 420/840 - Likewise, for the 2nd fraction, since 42 × 20 = 840,
9/42 = 9 × 20/42 × 20 = 180/840 - Add the two like fractions:
420/840 + 180/840 = 420 + 180/840 = 600/840 - 600/840 simplified gives 5/7
- So, 20/40 + 9/42 = 5/7
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