Subtract 28/30 from 15/42
15/42 - 28/30 is -121/210.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 30 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 42 × 5 = 210,
15/42 = 15 × 5/42 × 5 = 75/210 - Likewise, for the 2nd fraction, since 30 × 7 = 210,
28/30 = 28 × 7/30 × 7 = 196/210 - Subtract the two like fractions:
75/210 - 196/210 = 75 - 196/210 = -121/210
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