Subtract 16/40 from 5/21
5/21 - 16/40 is -17/105.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 21 × 40 = 840,
5/21 = 5 × 40/21 × 40 = 200/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
16/40 = 16 × 21/40 × 21 = 336/840 - Subtract the two like fractions:
200/840 - 336/840 = 200 - 336/840 = -136/840 - After reducing the fraction, the answer is -17/105
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