Subtract 18/40 from 30/21
1st number: 1 9/21, 2nd number: 18/40
30/21 - 18/40 is 137/140.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 21 × 40 = 840,
30/21 = 30 × 40/21 × 40 = 1200/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
18/40 = 18 × 21/40 × 21 = 378/840 - Subtract the two like fractions:
1200/840 - 378/840 = 1200 - 378/840 = 822/840 - After reducing the fraction, the answer is 137/140
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