Subtract 72/40 from 7/30, Solve 7/30

Subtract 72/40 from 7/30

1^st number: 7/30, 2^nd number: 1 32/40

7/30 - 72/40 is -47/30.

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,
7/30 = 7 × 4/30 × 4 = 28/120
Likewise, for the 2nd fraction, since 40 × 3 = 120,
72/40 = 72 × 3/40 × 3 = 216/120
Subtract the two like fractions:
28/120 - 216/120 = 28 - 216/120 = -188/120
After reducing the fraction, the answer is -47/30

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