Subtract 4/80 from 25/21, Solve 1 4/21

Subtract 4/80 from 25/21

1^st number: 1 4/21, 2^nd number: 4/80

25/21 - 4/80 is 479/420.

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,
25/21 = 25 × 80/21 × 80 = 2000/1680
Likewise, for the 2nd fraction, since 80 × 21 = 1680,
4/80 = 4 × 21/80 × 21 = 84/1680
Subtract the two like fractions:
2000/1680 - 84/1680 = 2000 - 84/1680 = 1916/1680
After reducing the fraction, the answer is 479/420
In mixed form: 159/420

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