Subtract 40/7 from 70/21
1st number: 3 7/21, 2nd number: 5 5/7
70/21 - 40/7 is -50/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 7 is 21
Next, find the equivalent fraction of both fractional numbers with denominator 21 - For the 1st fraction, since 21 × 1 = 21,
70/21 = 70 × 1/21 × 1 = 70/21 - Likewise, for the 2nd fraction, since 7 × 3 = 21,
40/7 = 40 × 3/7 × 3 = 120/21 - Subtract the two like fractions:
70/21 - 120/21 = 70 - 120/21 = -50/21
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