Subtract 72/42 from 75/10, Solve 7 5/10

Subtract 72/42 from 75/10

1^st number: 7 5/10, 2^nd number: 1 30/42

75/10 - 72/42 is 81/14.

Find the least common denominator or LCM of the two denominators:
LCM of 10 and 42 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 10 × 21 = 210,
75/10 = 75 × 21/10 × 21 = 1575/210
Likewise, for the 2nd fraction, since 42 × 5 = 210,
72/42 = 72 × 5/42 × 5 = 360/210
Subtract the two like fractions:
1575/210 - 360/210 = 1575 - 360/210 = 1215/210
After reducing the fraction, the answer is 81/14
In mixed form: 511/14

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