Add 21/40 and 12/42
21/40 + 12/42 is 227/280.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 42 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 40 × 21 = 840,
21/40 = 21 × 21/40 × 21 = 441/840 - Likewise, for the 2nd fraction, since 42 × 20 = 840,
12/42 = 12 × 20/42 × 20 = 240/840 - Add the two like fractions:
441/840 + 240/840 = 441 + 240/840 = 681/840 - 681/840 simplified gives 227/280
- So, 21/40 + 12/42 = 227/280
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