Add 7/20 and 27/42
7/20 + 27/42 is 139/140.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 42 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 20 × 21 = 420,
7/20 = 7 × 21/20 × 21 = 147/420 - Likewise, for the 2nd fraction, since 42 × 10 = 420,
27/42 = 27 × 10/42 × 10 = 270/420 - Add the two like fractions:
147/420 + 270/420 = 147 + 270/420 = 417/420 - 417/420 simplified gives 139/140
- So, 7/20 + 27/42 = 139/140
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