Add 12/21 and 28/40
12/21 + 28/40 is 89/70.
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,
28/40 = 28 × 21/40 × 21 = 588/840 - Add the two like fractions:
480/840 + 588/840 = 480 + 588/840 = 1068/840 - 1068/840 simplified gives 89/70
- So, 12/21 + 28/40 = 89/70
In mixed form: 119/70
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