Subtract 63/4 from 28/70, Solve 28/70

Subtract 63/4 from 28/70

1^st number: 28/70, 2^nd number: 15 3/4

28/70 - 63/4 is -307/20.

Find the least common denominator or LCM of the two denominators:
LCM of 70 and 4 is 140

Next, find the equivalent fraction of both fractional numbers with denominator 140
For the 1st fraction, since 70 × 2 = 140,
28/70 = 28 × 2/70 × 2 = 56/140
Likewise, for the 2nd fraction, since 4 × 35 = 140,
63/4 = 63 × 35/4 × 35 = 2205/140
Subtract the two like fractions:
56/140 - 2205/140 = 56 - 2205/140 = -2149/140
After reducing the fraction, the answer is -307/20

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