Subtract 30/90 from 18/7
1st number: 2 4/7, 2nd number: 30/90
18/7 - 30/90 is 47/21.
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,
30/90 = 30 × 7/90 × 7 = 210/630 - Subtract the two like fractions:
1620/630 - 210/630 = 1620 - 210/630 = 1410/630 - After reducing the fraction, the answer is 47/21
- In mixed form: 25/21
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