Subtract 75/6 from 21/40, Solve 21/40

Subtract 75/6 from 21/40

1^st number: 21/40, 2^nd number: 12 3/6

21/40 - 75/6 is -479/40.

Find the least common denominator or LCM of the two denominators:
LCM of 40 and 6 is 120

Next, find the equivalent fraction of both fractional numbers with denominator 120
For the 1st fraction, since 40 × 3 = 120,
21/40 = 21 × 3/40 × 3 = 63/120
Likewise, for the 2nd fraction, since 6 × 20 = 120,
75/6 = 75 × 20/6 × 20 = 1500/120
Subtract the two like fractions:
63/120 - 1500/120 = 63 - 1500/120 = -1437/120
After reducing the fraction, the answer is -479/40

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