Subtract 42/7 from 21/5
1st number: 4 1/5, 2nd number: 6 0/7
21/5 - 42/7 is -9/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 7 is 35
Next, find the equivalent fraction of both fractional numbers with denominator 35 - For the 1st fraction, since 5 × 7 = 35,
21/5 = 21 × 7/5 × 7 = 147/35 - Likewise, for the 2nd fraction, since 7 × 5 = 35,
42/7 = 42 × 5/7 × 5 = 210/35 - Subtract the two like fractions:
147/35 - 210/35 = 147 - 210/35 = -63/35 - After reducing the fraction, the answer is -9/5
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