Subtract 42/90 from 72/7, Solve 10 2/7

Subtract 42/90 from 72/7

1^st number: 10 2/7, 2^nd number: 42/90

72/7 - 42/90 is 1031/105.

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,
72/7 = 72 × 90/7 × 90 = 6480/630
Likewise, for the 2nd fraction, since 90 × 7 = 630,
42/90 = 42 × 7/90 × 7 = 294/630
Subtract the two like fractions:
6480/630 - 294/630 = 6480 - 294/630 = 6186/630
After reducing the fraction, the answer is 1031/105
In mixed form: 986/105

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