Subtract 30/70 from 42/21
1st number: 2 0/21, 2nd number: 30/70
42/21 - 30/70 is 11/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 70 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 70 × 3 = 210,
30/70 = 30 × 3/70 × 3 = 90/210 - Subtract the two like fractions:
420/210 - 90/210 = 420 - 90/210 = 330/210 - After reducing the fraction, the answer is 11/7
- In mixed form: 14/7
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