Subtract 40/42 from 30/15
1st number: 2 0/15, 2nd number: 40/42
30/15 - 40/42 is 22/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 42 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 15 × 14 = 210,
30/15 = 30 × 14/15 × 14 = 420/210 - Likewise, for the 2nd fraction, since 42 × 5 = 210,
40/42 = 40 × 5/42 × 5 = 200/210 - Subtract the two like fractions:
420/210 - 200/210 = 420 - 200/210 = 220/210 - After reducing the fraction, the answer is 22/21
- In mixed form: 11/21
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