Add 12/21 and 27/40
12/21 + 27/40 is 349/280.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 21 × 40 = 840,
12/21 = 12 × 40/21 × 40 = 480/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
27/40 = 27 × 21/40 × 21 = 567/840 - Add the two like fractions:
480/840 + 567/840 = 480 + 567/840 = 1047/840 - 1047/840 simplified gives 349/280
- So, 12/21 + 27/40 = 349/280
In mixed form: 169/280
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