Subtract 1/21 from 42/40
1st number: 1 2/40, 2nd number: 1/21
42/40 - 1/21 is 421/420.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 21 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 40 × 21 = 840,
42/40 = 42 × 21/40 × 21 = 882/840 - Likewise, for the 2nd fraction, since 21 × 40 = 840,
1/21 = 1 × 40/21 × 40 = 40/840 - Subtract the two like fractions:
882/840 - 40/840 = 882 - 40/840 = 842/840 - After reducing the fraction, the answer is 421/420
- In mixed form: 11/420
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