Subtract 30/21 from 72/70
1st number: 1 2/70, 2nd number: 1 9/21
72/70 - 30/21 is -2/5.
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,
72/70 = 72 × 3/70 × 3 = 216/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
30/21 = 30 × 10/21 × 10 = 300/210 - Subtract the two like fractions:
216/210 - 300/210 = 216 - 300/210 = -84/210 - After reducing the fraction, the answer is -2/5
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