Subtract 28/90 from 7/70
7/70 - 28/90 is -19/90.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 70 × 9 = 630,
7/70 = 7 × 9/70 × 9 = 63/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
28/90 = 28 × 7/90 × 7 = 196/630 - Subtract the two like fractions:
63/630 - 196/630 = 63 - 196/630 = -133/630 - After reducing the fraction, the answer is -19/90
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