Subtract 70/42 from 18/30
1st number: 18/30, 2nd number: 1 28/42
18/30 - 70/42 is -16/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 42 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 30 × 7 = 210,
18/30 = 18 × 7/30 × 7 = 126/210 - Likewise, for the 2nd fraction, since 42 × 5 = 210,
70/42 = 70 × 5/42 × 5 = 350/210 - Subtract the two like fractions:
126/210 - 350/210 = 126 - 350/210 = -224/210 - After reducing the fraction, the answer is -16/15
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