Subtract 21/20 from 30/4
1st number: 7 2/4, 2nd number: 1 1/20
30/4 - 21/20 is 129/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 20 is 20
Next, find the equivalent fraction of both fractional numbers with denominator 20 - For the 1st fraction, since 4 × 5 = 20,
30/4 = 30 × 5/4 × 5 = 150/20 - Likewise, for the 2nd fraction, since 20 × 1 = 20,
21/20 = 21 × 1/20 × 1 = 21/20 - Subtract the two like fractions:
150/20 - 21/20 = 150 - 21/20 = 129/20 - In mixed form: 69/20
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