Subtract 28/7 from 28/90
1st number: 28/90, 2nd number: 4 0/7
28/90 - 28/7 is -166/45.
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,
28/7 = 28 × 90/7 × 90 = 2520/630 - Subtract the two like fractions:
196/630 - 2520/630 = 196 - 2520/630 = -2324/630 - After reducing the fraction, the answer is -166/45
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