Subtract 63/40 from 90/84
1st number: 1 6/84, 2nd number: 1 23/40
90/84 - 63/40 is -141/280.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 84 × 10 = 840,
90/84 = 90 × 10/84 × 10 = 900/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
63/40 = 63 × 21/40 × 21 = 1323/840 - Subtract the two like fractions:
900/840 - 1323/840 = 900 - 1323/840 = -423/840 - After reducing the fraction, the answer is -141/280
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