Subtract 21/45 from 7/40
7/40 - 21/45 is -7/24.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 45 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 40 × 9 = 360,
7/40 = 7 × 9/40 × 9 = 63/360 - Likewise, for the 2nd fraction, since 45 × 8 = 360,
21/45 = 21 × 8/45 × 8 = 168/360 - Subtract the two like fractions:
63/360 - 168/360 = 63 - 168/360 = -105/360 - After reducing the fraction, the answer is -7/24
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