Subtract 21/40 from 15/9
1st number: 1 6/9, 2nd number: 21/40
15/9 - 21/40 is 137/120.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 40 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 9 × 40 = 360,
15/9 = 15 × 40/9 × 40 = 600/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
21/40 = 21 × 9/40 × 9 = 189/360 - Subtract the two like fractions:
600/360 - 189/360 = 600 - 189/360 = 411/360 - After reducing the fraction, the answer is 137/120
- In mixed form: 117/120
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