Answers

Subtract 81/70 from 90/40

1^st number: 2 10/40, 2^nd number: 1 11/70

90/40 - 81/70 is 153/140.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 40 and 70 is 280
   
   Next, find the equivalent fraction of both fractional numbers with denominator 280
2. For the 1st fraction, since 40 × 7 = 280,
   90/40 = 90 × 7/40 × 7 = 630/280
3. Likewise, for the 2nd fraction, since 70 × 4 = 280,
   81/70 = 81 × 4/70 × 4 = 324/280
4. Subtract the two like fractions:
   630/280 - 324/280 = 630 - 324/280 = 306/280
5. After reducing the fraction, the answer is 153/140
6. In mixed form: 113/140

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