Subtract 70/21 from 90/35
1st number: 2 20/35, 2nd number: 3 7/21
90/35 - 70/21 is -16/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 35 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 35 × 3 = 105,
90/35 = 90 × 3/35 × 3 = 270/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
70/21 = 70 × 5/21 × 5 = 350/105 - Subtract the two like fractions:
270/105 - 350/105 = 270 - 350/105 = -80/105 - After reducing the fraction, the answer is -16/21
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