Subtract 70/40 from 3/21
1st number: 3/21, 2nd number: 1 30/40
3/21 - 70/40 is -45/28.
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,
3/21 = 3 × 40/21 × 40 = 120/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
70/40 = 70 × 21/40 × 21 = 1470/840 - Subtract the two like fractions:
120/840 - 1470/840 = 120 - 1470/840 = -1350/840 - After reducing the fraction, the answer is -45/28
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