Subtract 50/90 from 80/42, Solve 1 38/42

Subtract 50/90 from 80/42

1^st number: 1 38/42, 2^nd number: 50/90

80/42 - 50/90 is 85/63.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 90 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 42 × 15 = 630,
80/42 = 80 × 15/42 × 15 = 1200/630
Likewise, for the 2nd fraction, since 90 × 7 = 630,
50/90 = 50 × 7/90 × 7 = 350/630
Subtract the two like fractions:
1200/630 - 350/630 = 1200 - 350/630 = 850/630
After reducing the fraction, the answer is 85/63
In mixed form: 122/63

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