Add 12/21 and 35/40
12/21 + 35/40 is 81/56.
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,
35/40 = 35 × 21/40 × 21 = 735/840 - Add the two like fractions:
480/840 + 735/840 = 480 + 735/840 = 1215/840 - 1215/840 simplified gives 81/56
- So, 12/21 + 35/40 = 81/56
In mixed form: 125/56
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