Add 40/42 and 20/84
40/42 + 20/84 is 25/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 84 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 42 × 2 = 84,
40/42 = 40 × 2/42 × 2 = 80/84 - Likewise, for the 2nd fraction, since 84 × 1 = 84,
20/84 = 20 × 1/84 × 1 = 20/84 - Add the two like fractions:
80/84 + 20/84 = 80 + 20/84 = 100/84 - 100/84 simplified gives 25/21
- So, 40/42 + 20/84 = 25/21
In mixed form: 14/21
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