Subtract 21/40 from 7/45
7/45 - 21/40 is -133/360.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 40 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 45 × 8 = 360,
7/45 = 7 × 8/45 × 8 = 56/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
21/40 = 21 × 9/40 × 9 = 189/360 - Subtract the two like fractions:
56/360 - 189/360 = 56 - 189/360 = -133/360
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