Subtract 90/8 from 21/50, Solve 21/50

Subtract 90/8 from 21/50

1^st number: 21/50, 2^nd number: 11 2/8

21/50 - 90/8 is -1083/100.

Find the least common denominator or LCM of the two denominators:
LCM of 50 and 8 is 200

Next, find the equivalent fraction of both fractional numbers with denominator 200
For the 1st fraction, since 50 × 4 = 200,
21/50 = 21 × 4/50 × 4 = 84/200
Likewise, for the 2nd fraction, since 8 × 25 = 200,
90/8 = 90 × 25/8 × 25 = 2250/200
Subtract the two like fractions:
84/200 - 2250/200 = 84 - 2250/200 = -2166/200
After reducing the fraction, the answer is -1083/100

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