Subtract 21/45 from 18/56
18/56 - 21/45 is -61/420.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 56 and 45 is 2520
Next, find the equivalent fraction of both fractional numbers with denominator 2520 - For the 1st fraction, since 56 × 45 = 2520,
18/56 = 18 × 45/56 × 45 = 810/2520 - Likewise, for the 2nd fraction, since 45 × 56 = 2520,
21/45 = 21 × 56/45 × 56 = 1176/2520 - Subtract the two like fractions:
810/2520 - 1176/2520 = 810 - 1176/2520 = -366/2520 - After reducing the fraction, the answer is -61/420
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