Add 40/42 and 18/21
40/42 + 18/21 is 38/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 21 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 42 × 1 = 42,
40/42 = 40 × 1/42 × 1 = 40/42 - Likewise, for the 2nd fraction, since 21 × 2 = 42,
18/21 = 18 × 2/21 × 2 = 36/42 - Add the two like fractions:
40/42 + 36/42 = 40 + 36/42 = 76/42 - 76/42 simplified gives 38/21
- So, 40/42 + 18/21 = 38/21
In mixed form: 117/21
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