Subtract 1/21 from 36/72
36/72 - 1/21 is 19/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 21 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 72 × 7 = 504,
36/72 = 36 × 7/72 × 7 = 252/504 - Likewise, for the 2nd fraction, since 21 × 24 = 504,
1/21 = 1 × 24/21 × 24 = 24/504 - Subtract the two like fractions:
252/504 - 24/504 = 252 - 24/504 = 228/504 - After reducing the fraction, the answer is 19/42
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