Subtract 42/21 from 28/30
1st number: 28/30, 2nd number: 2 0/21
28/30 - 42/21 is -16/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 21 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 21 × 10 = 210,
42/21 = 42 × 10/21 × 10 = 420/210 - Subtract the two like fractions:
196/210 - 420/210 = 196 - 420/210 = -224/210 - After reducing the fraction, the answer is -16/15
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