Subtract 1/40 from 72/30, Solve 2 12/30

Subtract 1/40 from 72/30

1^st number: 2 12/30, 2^nd number: 1/40

72/30 - 1/40 is 19/8.

Find the least common denominator or LCM of the two denominators:
LCM of 30 and 40 is 120

Next, find the equivalent fraction of both fractional numbers with denominator 120
For the 1st fraction, since 30 × 4 = 120,
72/30 = 72 × 4/30 × 4 = 288/120
Likewise, for the 2nd fraction, since 40 × 3 = 120,
1/40 = 1 × 3/40 × 3 = 3/120
Subtract the two like fractions:
288/120 - 3/120 = 288 - 3/120 = 285/120
After reducing the fraction, the answer is 19/8
In mixed form: 23/8

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