Subtract 21/90 from 40/12
1st number: 3 4/12, 2nd number: 21/90
40/12 - 21/90 is 31/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 90 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 12 × 15 = 180,
40/12 = 40 × 15/12 × 15 = 600/180 - Likewise, for the 2nd fraction, since 90 × 2 = 180,
21/90 = 21 × 2/90 × 2 = 42/180 - Subtract the two like fractions:
600/180 - 42/180 = 600 - 42/180 = 558/180 - After reducing the fraction, the answer is 31/10
- In mixed form: 31/10
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