Subtract 21/84 from 42/10
1st number: 4 2/10, 2nd number: 21/84
42/10 - 21/84 is 79/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 10 and 84 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 10 × 42 = 420,
42/10 = 42 × 42/10 × 42 = 1764/420 - Likewise, for the 2nd fraction, since 84 × 5 = 420,
21/84 = 21 × 5/84 × 5 = 105/420 - Subtract the two like fractions:
1764/420 - 105/420 = 1764 - 105/420 = 1659/420 - After reducing the fraction, the answer is 79/20
- In mixed form: 319/20
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