Add 42/84 and 21/20
1st number: 42/84, 2nd number: 1 1/20
42/84 + 21/20 is 31/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 20 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 84 × 5 = 420,
42/84 = 42 × 5/84 × 5 = 210/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
21/20 = 21 × 21/20 × 21 = 441/420 - Add the two like fractions:
210/420 + 441/420 = 210 + 441/420 = 651/420 - 651/420 simplified gives 31/20
- So, 42/84 + 21/20 = 31/20
In mixed form: 111/20
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