Subtract 90/21 from 72/20
1st number: 3 12/20, 2nd number: 4 6/21
72/20 - 90/21 is -24/35.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 21 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 20 × 21 = 420,
72/20 = 72 × 21/20 × 21 = 1512/420 - Likewise, for the 2nd fraction, since 21 × 20 = 420,
90/21 = 90 × 20/21 × 20 = 1800/420 - Subtract the two like fractions:
1512/420 - 1800/420 = 1512 - 1800/420 = -288/420 - After reducing the fraction, the answer is -24/35
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