Answers

Subtract 40/21 from 90/27

1^st number: 3 9/27, 2^nd number: 1 19/21

90/27 - 40/21 is 10/7.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 27 and 21 is 189
   
   Next, find the equivalent fraction of both fractional numbers with denominator 189
2. For the 1st fraction, since 27 × 7 = 189,
   90/27 = 90 × 7/27 × 7 = 630/189
3. Likewise, for the 2nd fraction, since 21 × 9 = 189,
   40/21 = 40 × 9/21 × 9 = 360/189
4. Subtract the two like fractions:
   630/189 - 360/189 = 630 - 360/189 = 270/189
5. After reducing the fraction, the answer is 10/7
6. In mixed form: 13/7

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