Subtract 21/7 from 18/5
1st number: 3 3/5, 2nd number: 3 0/7
18/5 - 21/7 is 3/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 7 is 35
Next, find the equivalent fraction of both fractional numbers with denominator 35 - For the 1st fraction, since 5 × 7 = 35,
18/5 = 18 × 7/5 × 7 = 126/35 - Likewise, for the 2nd fraction, since 7 × 5 = 35,
21/7 = 21 × 5/7 × 5 = 105/35 - Subtract the two like fractions:
126/35 - 105/35 = 126 - 105/35 = 21/35 - After reducing the fraction, the answer is 3/5
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