Subtract 70/63 from 81/40, Solve 2 1/40

Subtract 70/63 from 81/40

1^st number: 2 1/40, 2^nd number: 1 7/63

81/40 - 70/63 is 329/360.

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

Next, find the equivalent fraction of both fractional numbers with denominator 2520
For the 1st fraction, since 40 × 63 = 2520,
81/40 = 81 × 63/40 × 63 = 5103/2520
Likewise, for the 2nd fraction, since 63 × 40 = 2520,
70/63 = 70 × 40/63 × 40 = 2800/2520
Subtract the two like fractions:
5103/2520 - 2800/2520 = 5103 - 2800/2520 = 2303/2520
After reducing the fraction, the answer is 329/360

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