Subtract 70/21 from 90/30
1st number: 3 0/30, 2nd number: 3 7/21
90/30 - 70/21 is -1/3.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 21 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 30 × 7 = 210,
90/30 = 90 × 7/30 × 7 = 630/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
70/21 = 70 × 10/21 × 10 = 700/210 - Subtract the two like fractions:
630/210 - 700/210 = 630 - 700/210 = -70/210 - After reducing the fraction, the answer is -1/3
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