Subtract 63/40 from 30/63, Solve 30/63

Subtract 63/40 from 30/63

1^st number: 30/63, 2^nd number: 1 23/40

30/63 - 63/40 is -923/840.

Find the least common denominator or LCM of the two denominators:
LCM of 63 and 40 is 2520

Next, find the equivalent fraction of both fractional numbers with denominator 2520
For the 1st fraction, since 63 × 40 = 2520,
30/63 = 30 × 40/63 × 40 = 1200/2520
Likewise, for the 2nd fraction, since 40 × 63 = 2520,
63/40 = 63 × 63/40 × 63 = 3969/2520
Subtract the two like fractions:
1200/2520 - 3969/2520 = 1200 - 3969/2520 = -2769/2520
After reducing the fraction, the answer is -923/840

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