Subtract 21/5 from 9/42
1st number: 9/42, 2nd number: 4 1/5
9/42 - 21/5 is -279/70.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 5 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 42 × 5 = 210,
9/42 = 9 × 5/42 × 5 = 45/210 - Likewise, for the 2nd fraction, since 5 × 42 = 210,
21/5 = 21 × 42/5 × 42 = 882/210 - Subtract the two like fractions:
45/210 - 882/210 = 45 - 882/210 = -837/210 - After reducing the fraction, the answer is -279/70
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