Subtract 18/60 from 28/21
1st number: 1 7/21, 2nd number: 18/60
28/21 - 18/60 is 31/30.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 60 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 21 × 20 = 420,
28/21 = 28 × 20/21 × 20 = 560/420 - Likewise, for the 2nd fraction, since 60 × 7 = 420,
18/60 = 18 × 7/60 × 7 = 126/420 - Subtract the two like fractions:
560/420 - 126/420 = 560 - 126/420 = 434/420 - After reducing the fraction, the answer is 31/30
- In mixed form: 11/30
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