Add 45/42 and 21/12
1st number: 1 3/42, 2nd number: 1 9/12
45/42 + 21/12 is 79/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 12 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 42 × 2 = 84,
45/42 = 45 × 2/42 × 2 = 90/84 - Likewise, for the 2nd fraction, since 12 × 7 = 84,
21/12 = 21 × 7/12 × 7 = 147/84 - Add the two like fractions:
90/84 + 147/84 = 90 + 147/84 = 237/84 - 237/84 simplified gives 79/28
- So, 45/42 + 21/12 = 79/28
In mixed form: 223/28
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