Subtract 90/70 from 50/42
1st number: 1 8/42, 2nd number: 1 20/70
50/42 - 90/70 is -2/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 70 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 42 × 5 = 210,
50/42 = 50 × 5/42 × 5 = 250/210 - Likewise, for the 2nd fraction, since 70 × 3 = 210,
90/70 = 90 × 3/70 × 3 = 270/210 - Subtract the two like fractions:
250/210 - 270/210 = 250 - 270/210 = -20/210 - After reducing the fraction, the answer is -2/21
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