Subtract 70/90 from 18/7, Solve 2 4/7

Subtract 70/90 from 18/7

1^st number: 2 4/7, 2^nd number: 70/90

18/7 - 70/90 is 113/63.

Find the least common denominator or LCM of the two denominators:
LCM of 7 and 90 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 7 × 90 = 630,
18/7 = 18 × 90/7 × 90 = 1620/630
Likewise, for the 2nd fraction, since 90 × 7 = 630,
70/90 = 70 × 7/90 × 7 = 490/630
Subtract the two like fractions:
1620/630 - 490/630 = 1620 - 490/630 = 1130/630
After reducing the fraction, the answer is 113/63
In mixed form: 150/63

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