Subtract 70/30 from 30/21
1st number: 1 9/21, 2nd number: 2 10/30
30/21 - 70/30 is -19/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 30 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 21 × 10 = 210,
30/21 = 30 × 10/21 × 10 = 300/210 - Likewise, for the 2nd fraction, since 30 × 7 = 210,
70/30 = 70 × 7/30 × 7 = 490/210 - Subtract the two like fractions:
300/210 - 490/210 = 300 - 490/210 = -190/210 - After reducing the fraction, the answer is -19/21
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