Subtract 90/30 from 45/28
1st number: 1 17/28, 2nd number: 3 0/30
45/28 - 90/30 is -39/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 30 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 28 × 15 = 420,
45/28 = 45 × 15/28 × 15 = 675/420 - Likewise, for the 2nd fraction, since 30 × 14 = 420,
90/30 = 90 × 14/30 × 14 = 1260/420 - Subtract the two like fractions:
675/420 - 1260/420 = 675 - 1260/420 = -585/420 - After reducing the fraction, the answer is -39/28
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