Subtract 21/7 from 28/30
1st number: 28/30, 2nd number: 3 0/7
28/30 - 21/7 is -31/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 7 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 30 × 7 = 210,
28/30 = 28 × 7/30 × 7 = 196/210 - Likewise, for the 2nd fraction, since 7 × 30 = 210,
21/7 = 21 × 30/7 × 30 = 630/210 - Subtract the two like fractions:
196/210 - 630/210 = 196 - 630/210 = -434/210 - After reducing the fraction, the answer is -31/15
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