Add 20/42 and 21/7
1st number: 20/42, 2nd number: 3 0/7
20/42 + 21/7 is 73/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 7 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 42 × 1 = 42,
20/42 = 20 × 1/42 × 1 = 20/42 - Likewise, for the 2nd fraction, since 7 × 6 = 42,
21/7 = 21 × 6/7 × 6 = 126/42 - Add the two like fractions:
20/42 + 126/42 = 20 + 126/42 = 146/42 - 146/42 simplified gives 73/21
- So, 20/42 + 21/7 = 73/21
In mixed form: 310/21
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