Subtract 63/42 from 90/8, Solve 11 2/8

Subtract 63/42 from 90/8

1^st number: 11 2/8, 2^nd number: 1 21/42

90/8 - 63/42 is 39/4.

Find the least common denominator or LCM of the two denominators:
LCM of 8 and 42 is 168

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 8 × 21 = 168,
90/8 = 90 × 21/8 × 21 = 1890/168
Likewise, for the 2nd fraction, since 42 × 4 = 168,
63/42 = 63 × 4/42 × 4 = 252/168
Subtract the two like fractions:
1890/168 - 252/168 = 1890 - 252/168 = 1638/168
After reducing the fraction, the answer is 39/4
In mixed form: 93/4

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