Subtract 18/8 from 72/10, Solve 7 2/10

Subtract 18/8 from 72/10

1^st number: 7 2/10, 2^nd number: 2 2/8

72/10 - 18/8 is 99/20.

Find the least common denominator or LCM of the two denominators:
LCM of 10 and 8 is 40

Next, find the equivalent fraction of both fractional numbers with denominator 40
For the 1st fraction, since 10 × 4 = 40,
72/10 = 72 × 4/10 × 4 = 288/40
Likewise, for the 2nd fraction, since 8 × 5 = 40,
18/8 = 18 × 5/8 × 5 = 90/40
Subtract the two like fractions:
288/40 - 90/40 = 288 - 90/40 = 198/40
After reducing the fraction, the answer is 99/20
In mixed form: 419/20

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