Subtract 72/70 from 18/30
1st number: 18/30, 2nd number: 1 2/70
18/30 - 72/70 is -3/7.
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,
18/30 = 18 × 7/30 × 7 = 126/210 - Likewise, for the 2nd fraction, since 70 × 3 = 210,
72/70 = 72 × 3/70 × 3 = 216/210 - Subtract the two like fractions:
126/210 - 216/210 = 126 - 216/210 = -90/210 - After reducing the fraction, the answer is -3/7
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