Subtract 28/70 from 15/42
15/42 - 28/70 is -3/70.
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,
15/42 = 15 × 5/42 × 5 = 75/210 - Likewise, for the 2nd fraction, since 70 × 3 = 210,
28/70 = 28 × 3/70 × 3 = 84/210 - Subtract the two like fractions:
75/210 - 84/210 = 75 - 84/210 = -9/210 - After reducing the fraction, the answer is -3/70
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