Subtract 40/21 from 45/30
1st number: 1 15/30, 2nd number: 1 19/21
45/30 - 40/21 is -17/42.
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,
45/30 = 45 × 7/30 × 7 = 315/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
40/21 = 40 × 10/21 × 10 = 400/210 - Subtract the two like fractions:
315/210 - 400/210 = 315 - 400/210 = -85/210 - After reducing the fraction, the answer is -17/42
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