Add 12/80 and 42/21
1st number: 12/80, 2nd number: 2 0/21
12/80 + 42/21 is 43/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 21 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 80 × 21 = 1680,
12/80 = 12 × 21/80 × 21 = 252/1680 - Likewise, for the 2nd fraction, since 21 × 80 = 1680,
42/21 = 42 × 80/21 × 80 = 3360/1680 - Add the two like fractions:
252/1680 + 3360/1680 = 252 + 3360/1680 = 3612/1680 - 3612/1680 simplified gives 43/20
- So, 12/80 + 42/21 = 43/20
In mixed form: 23/20
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