Subtract 90/20 from 21/70
1st number: 21/70, 2nd number: 4 10/20
21/70 - 90/20 is -21/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 20 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 70 × 2 = 140,
21/70 = 21 × 2/70 × 2 = 42/140 - Likewise, for the 2nd fraction, since 20 × 7 = 140,
90/20 = 90 × 7/20 × 7 = 630/140 - Subtract the two like fractions:
42/140 - 630/140 = 42 - 630/140 = -588/140 - After reducing the fraction, the answer is -21/5
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