Subtract 30/80 from 21/10
1st number: 2 1/10, 2nd number: 30/80
21/10 - 30/80 is 69/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 10 and 80 is 80
Next, find the equivalent fraction of both fractional numbers with denominator 80 - For the 1st fraction, since 10 × 8 = 80,
21/10 = 21 × 8/10 × 8 = 168/80 - Likewise, for the 2nd fraction, since 80 × 1 = 80,
30/80 = 30 × 1/80 × 1 = 30/80 - Subtract the two like fractions:
168/80 - 30/80 = 168 - 30/80 = 138/80 - After reducing the fraction, the answer is 69/40
- In mixed form: 129/40
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