Subtract 15/45 from 90/70
1st number: 1 20/70, 2nd number: 15/45
90/70 - 15/45 is 20/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 45 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 70 × 9 = 630,
90/70 = 90 × 9/70 × 9 = 810/630 - Likewise, for the 2nd fraction, since 45 × 14 = 630,
15/45 = 15 × 14/45 × 14 = 210/630 - Subtract the two like fractions:
810/630 - 210/630 = 810 - 210/630 = 600/630 - After reducing the fraction, the answer is 20/21
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