Add 42/21 and 12/20
1st number: 2 0/21, 2nd number: 12/20
42/21 + 12/20 is 13/5.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 20 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 21 × 20 = 420,
42/21 = 42 × 20/21 × 20 = 840/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
12/20 = 12 × 21/20 × 21 = 252/420 - Add the two like fractions:
840/420 + 252/420 = 840 + 252/420 = 1092/420 - 1092/420 simplified gives 13/5
- So, 42/21 + 12/20 = 13/5
In mixed form: 23/5
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