Subtract 40/49 from 21/70
21/70 - 40/49 is -253/490.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 49 is 490
Next, find the equivalent fraction of both fractional numbers with denominator 490 - For the 1st fraction, since 70 × 7 = 490,
21/70 = 21 × 7/70 × 7 = 147/490 - Likewise, for the 2nd fraction, since 49 × 10 = 490,
40/49 = 40 × 10/49 × 10 = 400/490 - Subtract the two like fractions:
147/490 - 400/490 = 147 - 400/490 = -253/490
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