Subtract 6/40 from 54/21, Solve 2 12/21

Subtract 6/40 from 54/21

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

54/21 - 6/40 is 339/140.

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,
54/21 = 54 × 40/21 × 40 = 2160/840
Likewise, for the 2nd fraction, since 40 × 21 = 840,
6/40 = 6 × 21/40 × 21 = 126/840
Subtract the two like fractions:
2160/840 - 126/840 = 2160 - 126/840 = 2034/840
After reducing the fraction, the answer is 339/140
In mixed form: 259/140

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