Subtract 21/40 from 45/15
1st number: 3 0/15, 2nd number: 21/40
45/15 - 21/40 is 99/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 40 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 15 × 8 = 120,
45/15 = 45 × 8/15 × 8 = 360/120 - Likewise, for the 2nd fraction, since 40 × 3 = 120,
21/40 = 21 × 3/40 × 3 = 63/120 - Subtract the two like fractions:
360/120 - 63/120 = 360 - 63/120 = 297/120 - After reducing the fraction, the answer is 99/40
- In mixed form: 219/40
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