Subtract 42/90 from 84/18
1st number: 4 12/18, 2nd number: 42/90
84/18 - 42/90 is 21/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 90 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 18 × 5 = 90,
84/18 = 84 × 5/18 × 5 = 420/90 - Likewise, for the 2nd fraction, since 90 × 1 = 90,
42/90 = 42 × 1/90 × 1 = 42/90 - Subtract the two like fractions:
420/90 - 42/90 = 420 - 42/90 = 378/90 - After reducing the fraction, the answer is 21/5
- In mixed form: 41/5
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