Subtract 30/4 from 21/90
1st number: 21/90, 2nd number: 7 2/4
21/90 - 30/4 is -109/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 4 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 90 × 2 = 180,
21/90 = 21 × 2/90 × 2 = 42/180 - Likewise, for the 2nd fraction, since 4 × 45 = 180,
30/4 = 30 × 45/4 × 45 = 1350/180 - Subtract the two like fractions:
42/180 - 1350/180 = 42 - 1350/180 = -1308/180 - After reducing the fraction, the answer is -109/15
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