Subtract 18/21 from 16/20
16/20 - 18/21 is -2/35.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 21 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 20 × 21 = 420,
16/20 = 16 × 21/20 × 21 = 336/420 - Likewise, for the 2nd fraction, since 21 × 20 = 420,
18/21 = 18 × 20/21 × 20 = 360/420 - Subtract the two like fractions:
336/420 - 360/420 = 336 - 360/420 = -24/420 - After reducing the fraction, the answer is -2/35
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