Subtract 21/9 from 42/72
1st number: 42/72, 2nd number: 2 3/9
42/72 - 21/9 is -7/4.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 9 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 72 × 1 = 72,
42/72 = 42 × 1/72 × 1 = 42/72 - Likewise, for the 2nd fraction, since 9 × 8 = 72,
21/9 = 21 × 8/9 × 8 = 168/72 - Subtract the two like fractions:
42/72 - 168/72 = 42 - 168/72 = -126/72 - After reducing the fraction, the answer is -7/4
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