Subtract 42/16 from 30/70, Solve 30/70

Subtract 42/16 from 30/70

1^st number: 30/70, 2^nd number: 2 10/16

30/70 - 42/16 is -123/56.

Find the least common denominator or LCM of the two denominators:
LCM of 70 and 16 is 560

Next, find the equivalent fraction of both fractional numbers with denominator 560
For the 1st fraction, since 70 × 8 = 560,
30/70 = 30 × 8/70 × 8 = 240/560
Likewise, for the 2nd fraction, since 16 × 35 = 560,
42/16 = 42 × 35/16 × 35 = 1470/560
Subtract the two like fractions:
240/560 - 1470/560 = 240 - 1470/560 = -1230/560
After reducing the fraction, the answer is -123/56

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