Add 72/8 and 3/21, Solve 9 0/8 + 3/21 as a fraction

Add 72/8 and 3/21

1^st number: 9 0/8, 2^nd number: 3/21

72/8 + 3/21 is 64/7.

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,
3/21 = 3 × 8/21 × 8 = 24/168
Add the two like fractions:
1512/168 + 24/168 = 1512 + 24/168 = 1536/168
1536/168 simplified gives 64/7
So, 72/8 + 3/21 = 64/7
In mixed form: 91/7

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