Subtract 28/45 from 21/35
21/35 - 28/45 is -1/45.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 35 and 45 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 35 × 9 = 315,
21/35 = 21 × 9/35 × 9 = 189/315 - Likewise, for the 2nd fraction, since 45 × 7 = 315,
28/45 = 28 × 7/45 × 7 = 196/315 - Subtract the two like fractions:
189/315 - 196/315 = 189 - 196/315 = -7/315 - After reducing the fraction, the answer is -1/45
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