Subtract 90/42 from 90/21
1st number: 4 6/21, 2nd number: 2 6/42
90/21 - 90/42 is 15/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 42 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 21 × 2 = 42,
90/21 = 90 × 2/21 × 2 = 180/42 - Likewise, for the 2nd fraction, since 42 × 1 = 42,
90/42 = 90 × 1/42 × 1 = 90/42 - Subtract the two like fractions:
180/42 - 90/42 = 180 - 90/42 = 90/42 - After reducing the fraction, the answer is 15/7
- In mixed form: 21/7
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