Subtract 40/10 from 30/21
1st number: 1 9/21, 2nd number: 4 0/10
30/21 - 40/10 is -18/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 10 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 10 × 21 = 210,
40/10 = 40 × 21/10 × 21 = 840/210 - Subtract the two like fractions:
300/210 - 840/210 = 300 - 840/210 = -540/210 - After reducing the fraction, the answer is -18/7
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