Subtract 70/80 from 21/63
21/63 - 70/80 is -13/24.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 63 and 80 is 5040
Next, find the equivalent fraction of both fractional numbers with denominator 5040 - For the 1st fraction, since 63 × 80 = 5040,
21/63 = 21 × 80/63 × 80 = 1680/5040 - Likewise, for the 2nd fraction, since 80 × 63 = 5040,
70/80 = 70 × 63/80 × 63 = 4410/5040 - Subtract the two like fractions:
1680/5040 - 4410/5040 = 1680 - 4410/5040 = -2730/5040 - After reducing the fraction, the answer is -13/24
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Related: 42/63-70/80