Subtract 9/30 from 42/21
1st number: 2 0/21, 2nd number: 9/30
42/21 - 9/30 is 17/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 30 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 21 × 10 = 210,
42/21 = 42 × 10/21 × 10 = 420/210 - Likewise, for the 2nd fraction, since 30 × 7 = 210,
9/30 = 9 × 7/30 × 7 = 63/210 - Subtract the two like fractions:
420/210 - 63/210 = 420 - 63/210 = 357/210 - After reducing the fraction, the answer is 17/10
- In mixed form: 17/10
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