Subtract 21/42 from 70/45
1st number: 1 25/45, 2nd number: 21/42
70/45 - 21/42 is 19/18.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 42 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 45 × 14 = 630,
70/45 = 70 × 14/45 × 14 = 980/630 - Likewise, for the 2nd fraction, since 42 × 15 = 630,
21/42 = 21 × 15/42 × 15 = 315/630 - Subtract the two like fractions:
980/630 - 315/630 = 980 - 315/630 = 665/630 - After reducing the fraction, the answer is 19/18
- In mixed form: 11/18
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