Subtract 21/5 from 42/9
1st number: 4 6/9, 2nd number: 4 1/5
42/9 - 21/5 is 7/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 5 is 45
Next, find the equivalent fraction of both fractional numbers with denominator 45 - For the 1st fraction, since 9 × 5 = 45,
42/9 = 42 × 5/9 × 5 = 210/45 - Likewise, for the 2nd fraction, since 5 × 9 = 45,
21/5 = 21 × 9/5 × 9 = 189/45 - Subtract the two like fractions:
210/45 - 189/45 = 210 - 189/45 = 21/45 - After reducing the fraction, the answer is 7/15
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