Add 12/40 and 18/21
12/40 + 18/21 is 81/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 21 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 40 × 21 = 840,
12/40 = 12 × 21/40 × 21 = 252/840 - Likewise, for the 2nd fraction, since 21 × 40 = 840,
18/21 = 18 × 40/21 × 40 = 720/840 - Add the two like fractions:
252/840 + 720/840 = 252 + 720/840 = 972/840 - 972/840 simplified gives 81/70
- So, 12/40 + 18/21 = 81/70
In mixed form: 111/70
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