Add 72/8 and 28/21
1st number: 9 0/8, 2nd number: 1 7/21
72/8 + 28/21 is 31/3.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 21 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 8 × 21 = 168,
72/8 = 72 × 21/8 × 21 = 1512/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
28/21 = 28 × 8/21 × 8 = 224/168 - Add the two like fractions:
1512/168 + 224/168 = 1512 + 224/168 = 1736/168 - 1736/168 simplified gives 31/3
- So, 72/8 + 28/21 = 31/3
In mixed form: 101/3
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