Subtract 4/7 from 28/90
28/90 - 4/7 is -82/315.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 7 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 90 × 7 = 630,
28/90 = 28 × 7/90 × 7 = 196/630 - Likewise, for the 2nd fraction, since 7 × 90 = 630,
4/7 = 4 × 90/7 × 90 = 360/630 - Subtract the two like fractions:
196/630 - 360/630 = 196 - 360/630 = -164/630 - After reducing the fraction, the answer is -82/315
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