Add 72/42 and 20/84
1st number: 1 30/42, 2nd number: 20/84
72/42 + 20/84 is 41/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 84 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 42 × 2 = 84,
72/42 = 72 × 2/42 × 2 = 144/84 - Likewise, for the 2nd fraction, since 84 × 1 = 84,
20/84 = 20 × 1/84 × 1 = 20/84 - Add the two like fractions:
144/84 + 20/84 = 144 + 20/84 = 164/84 - 164/84 simplified gives 41/21
- So, 72/42 + 20/84 = 41/21
In mixed form: 120/21
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