Subtract 21/16 from 15/75, Solve 15/75

Subtract 21/16 from 15/75

1^st number: 15/75, 2^nd number: 1 5/16

15/75 - 21/16 is -89/80.

Find the least common denominator or LCM of the two denominators:
LCM of 75 and 16 is 1200

Next, find the equivalent fraction of both fractional numbers with denominator 1200
For the 1st fraction, since 75 × 16 = 1200,
15/75 = 15 × 16/75 × 16 = 240/1200
Likewise, for the 2nd fraction, since 16 × 75 = 1200,
21/16 = 21 × 75/16 × 75 = 1575/1200
Subtract the two like fractions:
240/1200 - 1575/1200 = 240 - 1575/1200 = -1335/1200
After reducing the fraction, the answer is -89/80

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