Subtract 18/7 from 21/45
1st number: 21/45, 2nd number: 2 4/7
21/45 - 18/7 is -221/105.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 7 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 45 × 7 = 315,
21/45 = 21 × 7/45 × 7 = 147/315 - Likewise, for the 2nd fraction, since 7 × 45 = 315,
18/7 = 18 × 45/7 × 45 = 810/315 - Subtract the two like fractions:
147/315 - 810/315 = 147 - 810/315 = -663/315 - After reducing the fraction, the answer is -221/105
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