Subtract 70/40 from 16/21
1st number: 16/21, 2nd number: 1 30/40
16/21 - 70/40 is -83/84.
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,
16/21 = 16 × 40/21 × 40 = 640/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
70/40 = 70 × 21/40 × 21 = 1470/840 - Subtract the two like fractions:
640/840 - 1470/840 = 640 - 1470/840 = -830/840 - After reducing the fraction, the answer is -83/84
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