Subtract 28/30 from 21/7
1st number: 3 0/7, 2nd number: 28/30
21/7 - 28/30 is 31/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 30 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 7 × 30 = 210,
21/7 = 21 × 30/7 × 30 = 630/210 - Likewise, for the 2nd fraction, since 30 × 7 = 210,
28/30 = 28 × 7/30 × 7 = 196/210 - Subtract the two like fractions:
630/210 - 196/210 = 630 - 196/210 = 434/210 - After reducing the fraction, the answer is 31/15
- In mixed form: 21/15
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