Subtract 42/21 from 15/4
1st number: 3 3/4, 2nd number: 2 0/21
15/4 - 42/21 is 7/4.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 4 × 21 = 84,
15/4 = 15 × 21/4 × 21 = 315/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
42/21 = 42 × 4/21 × 4 = 168/84 - Subtract the two like fractions:
315/84 - 168/84 = 315 - 168/84 = 147/84 - After reducing the fraction, the answer is 7/4
- In mixed form: 13/4
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