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

Subtract 25/80 from 4/21

4/21 - 25/80 is -41/336.

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,
4/21 = 4 × 80/21 × 80 = 320/1680
Likewise, for the 2nd fraction, since 80 × 21 = 1680,
25/80 = 25 × 21/80 × 21 = 525/1680
Subtract the two like fractions:
320/1680 - 525/1680 = 320 - 525/1680 = -205/1680
After reducing the fraction, the answer is -41/336

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