Add 7/21 and 40/42
7/21 + 40/42 is 9/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 42 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 21 × 2 = 42,
7/21 = 7 × 2/21 × 2 = 14/42 - Likewise, for the 2nd fraction, since 42 × 1 = 42,
40/42 = 40 × 1/42 × 1 = 40/42 - Add the two like fractions:
14/42 + 40/42 = 14 + 40/42 = 54/42 - 54/42 simplified gives 9/7
- So, 7/21 + 40/42 = 9/7
In mixed form: 12/7
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