Subtract 3/40 from 21/45
21/45 - 3/40 is 47/120.
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,
21/45 = 21 × 8/45 × 8 = 168/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
3/40 = 3 × 9/40 × 9 = 27/360 - Subtract the two like fractions:
168/360 - 27/360 = 168 - 27/360 = 141/360 - After reducing the fraction, the answer is 47/120
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