Answers

Subtract 15/40 from 90/42

1^st number: 2 6/42, 2^nd number: 15/40

90/42 - 15/40 is 99/56.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 42 and 40 is 840
   
   Next, find the equivalent fraction of both fractional numbers with denominator 840
2. For the 1st fraction, since 42 × 20 = 840,
   90/42 = 90 × 20/42 × 20 = 1800/840
3. Likewise, for the 2nd fraction, since 40 × 21 = 840,
   15/40 = 15 × 21/40 × 21 = 315/840
4. Subtract the two like fractions:
   1800/840 - 315/840 = 1800 - 315/840 = 1485/840
5. After reducing the fraction, the answer is 99/56
6. In mixed form: 143/56

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