Subtract 9/40 from 21/7
1st number: 3 0/7, 2nd number: 9/40
21/7 - 9/40 is 111/40.
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,
9/40 = 9 × 7/40 × 7 = 63/280 - Subtract the two like fractions:
840/280 - 63/280 = 840 - 63/280 = 777/280 - After reducing the fraction, the answer is 111/40
- In mixed form: 231/40
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