Subtract 84/45 from 21/30
1st number: 21/30, 2nd number: 1 39/45
21/30 - 84/45 is -7/6.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 45 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 30 × 3 = 90,
21/30 = 21 × 3/30 × 3 = 63/90 - Likewise, for the 2nd fraction, since 45 × 2 = 90,
84/45 = 84 × 2/45 × 2 = 168/90 - Subtract the two like fractions:
63/90 - 168/90 = 63 - 168/90 = -105/90 - After reducing the fraction, the answer is -7/6
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