Subtract 18/84 from 72/10, Solve 7 2/10

Subtract 18/84 from 72/10

1^st number: 7 2/10, 2^nd number: 18/84

72/10 - 18/84 is 489/70.

Find the least common denominator or LCM of the two denominators:
LCM of 10 and 84 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 10 × 42 = 420,
72/10 = 72 × 42/10 × 42 = 3024/420
Likewise, for the 2nd fraction, since 84 × 5 = 420,
18/84 = 18 × 5/84 × 5 = 90/420
Subtract the two like fractions:
3024/420 - 90/420 = 3024 - 90/420 = 2934/420
After reducing the fraction, the answer is 489/70
In mixed form: 669/70

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