Subtract 45/70 from 20/72
20/72 - 45/70 is -23/63.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 70 is 2520
Next, find the equivalent fraction of both fractional numbers with denominator 2520 - For the 1st fraction, since 72 × 35 = 2520,
20/72 = 20 × 35/72 × 35 = 700/2520 - Likewise, for the 2nd fraction, since 70 × 36 = 2520,
45/70 = 45 × 36/70 × 36 = 1620/2520 - Subtract the two like fractions:
700/2520 - 1620/2520 = 700 - 1620/2520 = -920/2520 - After reducing the fraction, the answer is -23/63
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