Answers

Subtract 21/84 from 70/80

70/80 - 21/84 is 5/8.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 80 and 84 is 1680
   
   Next, find the equivalent fraction of both fractional numbers with denominator 1680
2. For the 1st fraction, since 80 × 21 = 1680,
   70/80 = 70 × 21/80 × 21 = 1470/1680
3. Likewise, for the 2nd fraction, since 84 × 20 = 1680,
   21/84 = 21 × 20/84 × 20 = 420/1680
4. Subtract the two like fractions:
   1470/1680 - 420/1680 = 1470 - 420/1680 = 1050/1680
5. After reducing the fraction, the answer is 5/8

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