Subtract 70/15 from 28/40, Solve 28/40

Subtract 70/15 from 28/40

1^st number: 28/40, 2^nd number: 4 10/15

28/40 - 70/15 is -119/30.

Find the least common denominator or LCM of the two denominators:
LCM of 40 and 15 is 120

Next, find the equivalent fraction of both fractional numbers with denominator 120
For the 1st fraction, since 40 × 3 = 120,
28/40 = 28 × 3/40 × 3 = 84/120
Likewise, for the 2nd fraction, since 15 × 8 = 120,
70/15 = 70 × 8/15 × 8 = 560/120
Subtract the two like fractions:
84/120 - 560/120 = 84 - 560/120 = -476/120
After reducing the fraction, the answer is -119/30

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