Answers

Subtract 90/72 from 15/40

1^st number: 15/40, 2^nd number: 1 18/72

15/40 - 90/72 is -7/8.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 40 and 72 is 360
   
   Next, find the equivalent fraction of both fractional numbers with denominator 360
2. For the 1st fraction, since 40 × 9 = 360,
   15/40 = 15 × 9/40 × 9 = 135/360
3. Likewise, for the 2nd fraction, since 72 × 5 = 360,
   90/72 = 90 × 5/72 × 5 = 450/360
4. Subtract the two like fractions:
   135/360 - 450/360 = 135 - 450/360 = -315/360
5. After reducing the fraction, the answer is -7/8

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