Subtract 21/30 from 42/10
1st number: 4 2/10, 2nd number: 21/30
42/10 - 21/30 is 7/2.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 10 and 30 is 30
Next, find the equivalent fraction of both fractional numbers with denominator 30 - For the 1st fraction, since 10 × 3 = 30,
42/10 = 42 × 3/10 × 3 = 126/30 - Likewise, for the 2nd fraction, since 30 × 1 = 30,
21/30 = 21 × 1/30 × 1 = 21/30 - Subtract the two like fractions:
126/30 - 21/30 = 126 - 21/30 = 105/30 - After reducing the fraction, the answer is 7/2
- In mixed form: 31/2
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