Subtract 30/21 from 42/70
1st number: 42/70, 2nd number: 1 9/21
42/70 - 30/21 is -29/35.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 21 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 70 × 3 = 210,
42/70 = 42 × 3/70 × 3 = 126/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
30/21 = 30 × 10/21 × 10 = 300/210 - Subtract the two like fractions:
126/210 - 300/210 = 126 - 300/210 = -174/210 - After reducing the fraction, the answer is -29/35
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