Subtract 21/90 from 18/7
1st number: 2 4/7, 2nd number: 21/90
18/7 - 21/90 is 491/210.
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,
18/7 = 18 × 90/7 × 90 = 1620/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
21/90 = 21 × 7/90 × 7 = 147/630 - Subtract the two like fractions:
1620/630 - 147/630 = 1620 - 147/630 = 1473/630 - After reducing the fraction, the answer is 491/210
- In mixed form: 271/210
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