Subtract 70/90 from 72/70, Solve 1 2/70

Subtract 70/90 from 72/70

1^st number: 1 2/70, 2^nd number: 70/90

72/70 - 70/90 is 79/315.

Find the least common denominator or LCM of the two denominators:
LCM of 70 and 90 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 70 × 9 = 630,
72/70 = 72 × 9/70 × 9 = 648/630
Likewise, for the 2nd fraction, since 90 × 7 = 630,
70/90 = 70 × 7/90 × 7 = 490/630
Subtract the two like fractions:
648/630 - 490/630 = 648 - 490/630 = 158/630
After reducing the fraction, the answer is 79/315

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