Subtract 1/40 from 21/84
21/84 - 1/40 is 9/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 84 × 10 = 840,
21/84 = 21 × 10/84 × 10 = 210/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
1/40 = 1 × 21/40 × 21 = 21/840 - Subtract the two like fractions:
210/840 - 21/840 = 210 - 21/840 = 189/840 - After reducing the fraction, the answer is 9/40
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