Subtract 40/45 from 21/49
21/49 - 40/45 is -29/63.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 49 and 45 is 2205
Next, find the equivalent fraction of both fractional numbers with denominator 2205 - For the 1st fraction, since 49 × 45 = 2205,
21/49 = 21 × 45/49 × 45 = 945/2205 - Likewise, for the 2nd fraction, since 45 × 49 = 2205,
40/45 = 40 × 49/45 × 49 = 1960/2205 - Subtract the two like fractions:
945/2205 - 1960/2205 = 945 - 1960/2205 = -1015/2205 - After reducing the fraction, the answer is -29/63
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