Subtract 7/70 from 20/45
20/45 - 7/70 is 31/90.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 70 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 45 × 14 = 630,
20/45 = 20 × 14/45 × 14 = 280/630 - Likewise, for the 2nd fraction, since 70 × 9 = 630,
7/70 = 7 × 9/70 × 9 = 63/630 - Subtract the two like fractions:
280/630 - 63/630 = 280 - 63/630 = 217/630 - After reducing the fraction, the answer is 31/90
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