Subtract 21/7 from 40/70
1st number: 40/70, 2nd number: 3 0/7
40/70 - 21/7 is -17/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 7 is 70
Next, find the equivalent fraction of both fractional numbers with denominator 70 - For the 1st fraction, since 70 × 1 = 70,
40/70 = 40 × 1/70 × 1 = 40/70 - Likewise, for the 2nd fraction, since 7 × 10 = 70,
21/7 = 21 × 10/7 × 10 = 210/70 - Subtract the two like fractions:
40/70 - 210/70 = 40 - 210/70 = -170/70 - After reducing the fraction, the answer is -17/7
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