Subtract 21/70 from 9/42
9/42 - 21/70 is -3/35.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 70 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 70 × 3 = 210,
21/70 = 21 × 3/70 × 3 = 63/210 - Subtract the two like fractions:
45/210 - 63/210 = 45 - 63/210 = -18/210 - After reducing the fraction, the answer is -3/35
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