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