Add 42/3 and 72/21
1st number: 14 0/3, 2nd number: 3 9/21
42/3 + 72/21 is 122/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 3 and 21 is 21
Next, find the equivalent fraction of both fractional numbers with denominator 21 - For the 1st fraction, since 3 × 7 = 21,
42/3 = 42 × 7/3 × 7 = 294/21 - Likewise, for the 2nd fraction, since 21 × 1 = 21,
72/21 = 72 × 1/21 × 1 = 72/21 - Add the two like fractions:
294/21 + 72/21 = 294 + 72/21 = 366/21 - 366/21 simplified gives 122/7
- So, 42/3 + 72/21 = 122/7
In mixed form: 173/7
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