Subtract 45/40 from 21/7
1st number: 3 0/7, 2nd number: 1 5/40
21/7 - 45/40 is 15/8.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 40 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 7 × 40 = 280,
21/7 = 21 × 40/7 × 40 = 840/280 - Likewise, for the 2nd fraction, since 40 × 7 = 280,
45/40 = 45 × 7/40 × 7 = 315/280 - Subtract the two like fractions:
840/280 - 315/280 = 840 - 315/280 = 525/280 - After reducing the fraction, the answer is 15/8
- In mixed form: 17/8
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