Subtract 21/42 from 90/30
1st number: 3 0/30, 2nd number: 21/42
90/30 - 21/42 is 5/2.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 42 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 30 × 7 = 210,
90/30 = 90 × 7/30 × 7 = 630/210 - Likewise, for the 2nd fraction, since 42 × 5 = 210,
21/42 = 21 × 5/42 × 5 = 105/210 - Subtract the two like fractions:
630/210 - 105/210 = 630 - 105/210 = 525/210 - After reducing the fraction, the answer is 5/2
- In mixed form: 21/2
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