Subtract 4/20 from 40/21, Solve 1 19/21

Subtract 4/20 from 40/21

1^st number: 1 19/21, 2^nd number: 4/20

40/21 - 4/20 is 179/105.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 20 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 21 × 20 = 420,
40/21 = 40 × 20/21 × 20 = 800/420
Likewise, for the 2nd fraction, since 20 × 21 = 420,
4/20 = 4 × 21/20 × 21 = 84/420
Subtract the two like fractions:
800/420 - 84/420 = 800 - 84/420 = 716/420
After reducing the fraction, the answer is 179/105
In mixed form: 174/105

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