Subtract 30/10 from 28/21
1st number: 1 7/21, 2nd number: 3 0/10
28/21 - 30/10 is -5/3.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 10 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 21 × 10 = 210,
28/21 = 28 × 10/21 × 10 = 280/210 - Likewise, for the 2nd fraction, since 10 × 21 = 210,
30/10 = 30 × 21/10 × 21 = 630/210 - Subtract the two like fractions:
280/210 - 630/210 = 280 - 630/210 = -350/210 - After reducing the fraction, the answer is -5/3
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