Subtract 1/90 from 45/70
45/70 - 1/90 is 199/315.
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,
45/70 = 45 × 9/70 × 9 = 405/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
1/90 = 1 × 7/90 × 7 = 7/630 - Subtract the two like fractions:
405/630 - 7/630 = 405 - 7/630 = 398/630 - After reducing the fraction, the answer is 199/315
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