Subtract 21/49 from 7/45
7/45 - 21/49 is -86/315.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 49 is 2205
Next, find the equivalent fraction of both fractional numbers with denominator 2205 - For the 1st fraction, since 45 × 49 = 2205,
7/45 = 7 × 49/45 × 49 = 343/2205 - Likewise, for the 2nd fraction, since 49 × 45 = 2205,
21/49 = 21 × 45/49 × 45 = 945/2205 - Subtract the two like fractions:
343/2205 - 945/2205 = 343 - 945/2205 = -602/2205 - After reducing the fraction, the answer is -86/315
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