Subtract 30/21 from 1/40
1st number: 1/40, 2nd number: 1 9/21
1/40 - 30/21 is -393/280.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 21 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 40 × 21 = 840,
1/40 = 1 × 21/40 × 21 = 21/840 - Likewise, for the 2nd fraction, since 21 × 40 = 840,
30/21 = 30 × 40/21 × 40 = 1200/840 - Subtract the two like fractions:
21/840 - 1200/840 = 21 - 1200/840 = -1179/840 - After reducing the fraction, the answer is -393/280
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