Subtract 90/4 from 21/75, Solve 21/75

Subtract 90/4 from 21/75

1^st number: 21/75, 2^nd number: 22 2/4

21/75 - 90/4 is -1111/50.

Find the least common denominator or LCM of the two denominators:
LCM of 75 and 4 is 300

Next, find the equivalent fraction of both fractional numbers with denominator 300
For the 1st fraction, since 75 × 4 = 300,
21/75 = 21 × 4/75 × 4 = 84/300
Likewise, for the 2nd fraction, since 4 × 75 = 300,
90/4 = 90 × 75/4 × 75 = 6750/300
Subtract the two like fractions:
84/300 - 6750/300 = 84 - 6750/300 = -6666/300
After reducing the fraction, the answer is -1111/50

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