Subtract 90/80 from 42/15
1st number: 2 12/15, 2nd number: 1 10/80
42/15 - 90/80 is 67/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 80 is 240
Next, find the equivalent fraction of both fractional numbers with denominator 240 - For the 1st fraction, since 15 × 16 = 240,
42/15 = 42 × 16/15 × 16 = 672/240 - Likewise, for the 2nd fraction, since 80 × 3 = 240,
90/80 = 90 × 3/80 × 3 = 270/240 - Subtract the two like fractions:
672/240 - 270/240 = 672 - 270/240 = 402/240 - After reducing the fraction, the answer is 67/40
- In mixed form: 127/40
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