Add 4/42 and 18/21
4/42 + 18/21 is 20/21.
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,
4/42 = 4 × 1/42 × 1 = 4/42 - Likewise, for the 2nd fraction, since 21 × 2 = 42,
18/21 = 18 × 2/21 × 2 = 36/42 - Add the two like fractions:
4/42 + 36/42 = 4 + 36/42 = 40/42 - 40/42 simplified gives 20/21
- So, 4/42 + 18/21 = 20/21
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