Subtract 28/90 from 2/21
2/21 - 28/90 is -68/315.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 21 × 30 = 630,
2/21 = 2 × 30/21 × 30 = 60/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
28/90 = 28 × 7/90 × 7 = 196/630 - Subtract the two like fractions:
60/630 - 196/630 = 60 - 196/630 = -136/630 - After reducing the fraction, the answer is -68/315
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