Subtract 18/24 from 21/70
21/70 - 18/24 is -9/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 24 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 70 × 12 = 840,
21/70 = 21 × 12/70 × 12 = 252/840 - Likewise, for the 2nd fraction, since 24 × 35 = 840,
18/24 = 18 × 35/24 × 35 = 630/840 - Subtract the two like fractions:
252/840 - 630/840 = 252 - 630/840 = -378/840 - After reducing the fraction, the answer is -9/20
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