Answers

Subtract 21/36 from 30/72

30/72 - 21/36 is -1/6.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 72 and 36 is 72
   
   Next, find the equivalent fraction of both fractional numbers with denominator 72
2. For the 1st fraction, since 72 × 1 = 72,
   30/72 = 30 × 1/72 × 1 = 30/72
3. Likewise, for the 2nd fraction, since 36 × 2 = 72,
   21/36 = 21 × 2/36 × 2 = 42/72
4. Subtract the two like fractions:
   30/72 - 42/72 = 30 - 42/72 = -12/72
5. After reducing the fraction, the answer is -1/6

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