Subtract 4/30 from 42/21
1st number: 2 0/21, 2nd number: 4/30
42/21 - 4/30 is 28/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 30 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 21 × 10 = 210,
42/21 = 42 × 10/21 × 10 = 420/210 - Likewise, for the 2nd fraction, since 30 × 7 = 210,
4/30 = 4 × 7/30 × 7 = 28/210 - Subtract the two like fractions:
420/210 - 28/210 = 420 - 28/210 = 392/210 - After reducing the fraction, the answer is 28/15
- In mixed form: 113/15
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