Subtract 42/90 from 21/7
1st number: 3 0/7, 2nd number: 42/90
21/7 - 42/90 is 38/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 7 × 90 = 630,
21/7 = 21 × 90/7 × 90 = 1890/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
42/90 = 42 × 7/90 × 7 = 294/630 - Subtract the two like fractions:
1890/630 - 294/630 = 1890 - 294/630 = 1596/630 - After reducing the fraction, the answer is 38/15
- In mixed form: 28/15
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