Subtract 3/40 from 63/21, Solve 3 0/21

Subtract 3/40 from 63/21

1^st number: 3 0/21, 2^nd number: 3/40

63/21 - 3/40 is 117/40.

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

Next, find the equivalent fraction of both fractional numbers with denominator 840
For the 1st fraction, since 21 × 40 = 840,
63/21 = 63 × 40/21 × 40 = 2520/840
Likewise, for the 2nd fraction, since 40 × 21 = 840,
3/40 = 3 × 21/40 × 21 = 63/840
Subtract the two like fractions:
2520/840 - 63/840 = 2520 - 63/840 = 2457/840
After reducing the fraction, the answer is 117/40
In mixed form: 237/40

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