Subtract 42/90 from 21/4
1st number: 5 1/4, 2nd number: 42/90
21/4 - 42/90 is 287/60.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 90 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 4 × 45 = 180,
21/4 = 21 × 45/4 × 45 = 945/180 - Likewise, for the 2nd fraction, since 90 × 2 = 180,
42/90 = 42 × 2/90 × 2 = 84/180 - Subtract the two like fractions:
945/180 - 84/180 = 945 - 84/180 = 861/180 - After reducing the fraction, the answer is 287/60
- In mixed form: 447/60
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