Subtract 21/15 from 18/70
1st number: 18/70, 2nd number: 1 6/15
18/70 - 21/15 is -8/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 15 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 70 × 3 = 210,
18/70 = 18 × 3/70 × 3 = 54/210 - Likewise, for the 2nd fraction, since 15 × 14 = 210,
21/15 = 21 × 14/15 × 14 = 294/210 - Subtract the two like fractions:
54/210 - 294/210 = 54 - 294/210 = -240/210 - After reducing the fraction, the answer is -8/7
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