Subtract 70/3 from 21/70, Solve 21/70

Subtract 70/3 from 21/70

1^st number: 21/70, 2^nd number: 23 1/3

21/70 - 70/3 is -691/30.

Find the least common denominator or LCM of the two denominators:
LCM of 70 and 3 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 70 × 3 = 210,
21/70 = 21 × 3/70 × 3 = 63/210
Likewise, for the 2nd fraction, since 3 × 70 = 210,
70/3 = 70 × 70/3 × 70 = 4900/210
Subtract the two like fractions:
63/210 - 4900/210 = 63 - 4900/210 = -4837/210
After reducing the fraction, the answer is -691/30

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