Subtract 18/28 from 42/70
42/70 - 18/28 is -3/70.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 28 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 70 × 2 = 140,
42/70 = 42 × 2/70 × 2 = 84/140 - Likewise, for the 2nd fraction, since 28 × 5 = 140,
18/28 = 18 × 5/28 × 5 = 90/140 - Subtract the two like fractions:
84/140 - 90/140 = 84 - 90/140 = -6/140 - After reducing the fraction, the answer is -3/70
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