Subtract 21/42 from 90/70
1st number: 1 20/70, 2nd number: 21/42
90/70 - 21/42 is 11/14.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 42 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 70 × 3 = 210,
90/70 = 90 × 3/70 × 3 = 270/210 - Likewise, for the 2nd fraction, since 42 × 5 = 210,
21/42 = 21 × 5/42 × 5 = 105/210 - Subtract the two like fractions:
270/210 - 105/210 = 270 - 105/210 = 165/210 - After reducing the fraction, the answer is 11/14
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