Subtract 42/70 from 12/30
12/30 - 42/70 is -1/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 70 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 30 × 7 = 210,
12/30 = 12 × 7/30 × 7 = 84/210 - Likewise, for the 2nd fraction, since 70 × 3 = 210,
42/70 = 42 × 3/70 × 3 = 126/210 - Subtract the two like fractions:
84/210 - 126/210 = 84 - 126/210 = -42/210 - After reducing the fraction, the answer is -1/5
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