Subtract 4/90 from 42/45
42/45 - 4/90 is 8/9.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 90 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 45 × 2 = 90,
42/45 = 42 × 2/45 × 2 = 84/90 - Likewise, for the 2nd fraction, since 90 × 1 = 90,
4/90 = 4 × 1/90 × 1 = 4/90 - Subtract the two like fractions:
84/90 - 4/90 = 84 - 4/90 = 80/90 - After reducing the fraction, the answer is 8/9
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