Subtract 21/45 from 21/7
1st number: 3 0/7, 2nd number: 21/45
21/7 - 21/45 is 38/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 45 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 7 × 45 = 315,
21/7 = 21 × 45/7 × 45 = 945/315 - Likewise, for the 2nd fraction, since 45 × 7 = 315,
21/45 = 21 × 7/45 × 7 = 147/315 - Subtract the two like fractions:
945/315 - 147/315 = 945 - 147/315 = 798/315 - After reducing the fraction, the answer is 38/15
- In mixed form: 28/15
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