Subtract 4/21 from 10/8, Solve 1 2/8

Subtract 4/21 from 10/8

1^st number: 1 2/8, 2^nd number: 4/21

10/8 - 4/21 is 89/84.

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,
10/8 = 10 × 21/8 × 21 = 210/168
Likewise, for the 2nd fraction, since 21 × 8 = 168,
4/21 = 4 × 8/21 × 8 = 32/168
Subtract the two like fractions:
210/168 - 32/168 = 210 - 32/168 = 178/168
After reducing the fraction, the answer is 89/84
In mixed form: 15/84

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