Subtract 21/42 from 90/15
1st number: 6 0/15, 2nd number: 21/42
90/15 - 21/42 is 11/2.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 42 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 15 × 14 = 210,
90/15 = 90 × 14/15 × 14 = 1260/210 - Likewise, for the 2nd fraction, since 42 × 5 = 210,
21/42 = 21 × 5/42 × 5 = 105/210 - Subtract the two like fractions:
1260/210 - 105/210 = 1260 - 105/210 = 1155/210 - After reducing the fraction, the answer is 11/2
- In mixed form: 51/2
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