Add 72/42 and 84/21
1st number: 1 30/42, 2nd number: 4 0/21
72/42 + 84/21 is 40/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 21 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 42 × 1 = 42,
72/42 = 72 × 1/42 × 1 = 72/42 - Likewise, for the 2nd fraction, since 21 × 2 = 42,
84/21 = 84 × 2/21 × 2 = 168/42 - Add the two like fractions:
72/42 + 168/42 = 72 + 168/42 = 240/42 - 240/42 simplified gives 40/7
- So, 72/42 + 84/21 = 40/7
In mixed form: 55/7
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