Subtract 4/40 from 21/18
1st number: 1 3/18, 2nd number: 4/40
21/18 - 4/40 is 16/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 40 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 18 × 20 = 360,
21/18 = 21 × 20/18 × 20 = 420/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
4/40 = 4 × 9/40 × 9 = 36/360 - Subtract the two like fractions:
420/360 - 36/360 = 420 - 36/360 = 384/360 - After reducing the fraction, the answer is 16/15
- In mixed form: 11/15
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