Subtract 4/40 from 40/21, Solve 1 19/21

Subtract 4/40 from 40/21

1^st number: 1 19/21, 2^nd number: 4/40

40/21 - 4/40 is 379/210.

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,
40/21 = 40 × 40/21 × 40 = 1600/840
Likewise, for the 2nd fraction, since 40 × 21 = 840,
4/40 = 4 × 21/40 × 21 = 84/840
Subtract the two like fractions:
1600/840 - 84/840 = 1600 - 84/840 = 1516/840
After reducing the fraction, the answer is 379/210
In mixed form: 1169/210

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