Subtract 21/8 from 7/84, Solve 7/84

Subtract 21/8 from 7/84

1^st number: 7/84, 2^nd number: 2 5/8

7/84 - 21/8 is -61/24.

Find the least common denominator or LCM of the two denominators:
LCM of 84 and 8 is 168

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 84 × 2 = 168,
7/84 = 7 × 2/84 × 2 = 14/168
Likewise, for the 2nd fraction, since 8 × 21 = 168,
21/8 = 21 × 21/8 × 21 = 441/168
Subtract the two like fractions:
14/168 - 441/168 = 14 - 441/168 = -427/168
After reducing the fraction, the answer is -61/24

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