Add 72/8 and 42/21, Solve 9 0/8 + 2 0/21 as a fraction

Add 72/8 and 42/21

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

72/8 + 42/21 is 11/1.

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,
42/21 = 42 × 8/21 × 8 = 336/168
Add the two like fractions:
1512/168 + 336/168 = 1512 + 336/168 = 1848/168
1848/168 simplified gives 11/1
So, 72/8 + 42/21 = 11/1

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