Subtract 15/70 from 21/18
1st number: 1 3/18, 2nd number: 15/70
21/18 - 15/70 is 20/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 70 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 18 × 35 = 630,
21/18 = 21 × 35/18 × 35 = 735/630 - Likewise, for the 2nd fraction, since 70 × 9 = 630,
15/70 = 15 × 9/70 × 9 = 135/630 - Subtract the two like fractions:
735/630 - 135/630 = 735 - 135/630 = 600/630 - After reducing the fraction, the answer is 20/21
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