Add 21/42 and 12/7
1st number: 21/42, 2nd number: 1 5/7
21/42 + 12/7 is 31/14.
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,
21/42 = 21 × 1/42 × 1 = 21/42 - Likewise, for the 2nd fraction, since 7 × 6 = 42,
12/7 = 12 × 6/7 × 6 = 72/42 - Add the two like fractions:
21/42 + 72/42 = 21 + 72/42 = 93/42 - 93/42 simplified gives 31/14
- So, 21/42 + 12/7 = 31/14
In mixed form: 23/14
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