Subtract 5/80 from 40/21, Solve 1 19/21

Subtract 5/80 from 40/21

1^st number: 1 19/21, 2^nd number: 5/80

40/21 - 5/80 is 619/336.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 80 is 1680

Next, find the equivalent fraction of both fractional numbers with denominator 1680
For the 1st fraction, since 21 × 80 = 1680,
40/21 = 40 × 80/21 × 80 = 3200/1680
Likewise, for the 2nd fraction, since 80 × 21 = 1680,
5/80 = 5 × 21/80 × 21 = 105/1680
Subtract the two like fractions:
3200/1680 - 105/1680 = 3200 - 105/1680 = 3095/1680
After reducing the fraction, the answer is 619/336
In mixed form: 1283/336

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