Answers

Subtract 90/30 from 40/70

1^st number: 40/70, 2^nd number: 3 0/30

40/70 - 90/30 is -17/7.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 70 and 30 is 210
   
   Next, find the equivalent fraction of both fractional numbers with denominator 210
2. For the 1st fraction, since 70 × 3 = 210,
   40/70 = 40 × 3/70 × 3 = 120/210
3. Likewise, for the 2nd fraction, since 30 × 7 = 210,
   90/30 = 90 × 7/30 × 7 = 630/210
4. Subtract the two like fractions:
   120/210 - 630/210 = 120 - 630/210 = -510/210
5. After reducing the fraction, the answer is -17/7

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