Subtract 9/21 from 63/40, Solve 1 23/40

Subtract 9/21 from 63/40

1^st number: 1 23/40, 2^nd number: 9/21

63/40 - 9/21 is 321/280.

Find the least common denominator or LCM of the two denominators:
LCM of 40 and 21 is 840

Next, find the equivalent fraction of both fractional numbers with denominator 840
For the 1st fraction, since 40 × 21 = 840,
63/40 = 63 × 21/40 × 21 = 1323/840
Likewise, for the 2nd fraction, since 21 × 40 = 840,
9/21 = 9 × 40/21 × 40 = 360/840
Subtract the two like fractions:
1323/840 - 360/840 = 1323 - 360/840 = 963/840
After reducing the fraction, the answer is 321/280
In mixed form: 141/280

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