Subtract 20/40 from 30/63
30/63 - 20/40 is -1/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 63 and 40 is 2520
Next, find the equivalent fraction of both fractional numbers with denominator 2520 - For the 1st fraction, since 63 × 40 = 2520,
30/63 = 30 × 40/63 × 40 = 1200/2520 - Likewise, for the 2nd fraction, since 40 × 63 = 2520,
20/40 = 20 × 63/40 × 63 = 1260/2520 - Subtract the two like fractions:
1200/2520 - 1260/2520 = 1200 - 1260/2520 = -60/2520 - After reducing the fraction, the answer is -1/42
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