Subtract 16/21 from 21/35
21/35 - 16/21 is -17/105.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 35 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 35 × 3 = 105,
21/35 = 21 × 3/35 × 3 = 63/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
16/21 = 16 × 5/21 × 5 = 80/105 - Subtract the two like fractions:
63/105 - 80/105 = 63 - 80/105 = -17/105
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