Subtract 90/21 from 30/90
1st number: 30/90, 2nd number: 4 6/21
30/90 - 90/21 is -83/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 21 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 90 × 7 = 630,
30/90 = 30 × 7/90 × 7 = 210/630 - Likewise, for the 2nd fraction, since 21 × 30 = 630,
90/21 = 90 × 30/21 × 30 = 2700/630 - Subtract the two like fractions:
210/630 - 2700/630 = 210 - 2700/630 = -2490/630 - After reducing the fraction, the answer is -83/21
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