Subtract 21/42 from 12/5
1st number: 2 2/5, 2nd number: 21/42
12/5 - 21/42 is 19/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 42 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 5 × 42 = 210,
12/5 = 12 × 42/5 × 42 = 504/210 - Likewise, for the 2nd fraction, since 42 × 5 = 210,
21/42 = 21 × 5/42 × 5 = 105/210 - Subtract the two like fractions:
504/210 - 105/210 = 504 - 105/210 = 399/210 - After reducing the fraction, the answer is 19/10
- In mixed form: 19/10
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