Subtract 70/5 from 30/21, Solve 1 9/21

Subtract 70/5 from 30/21

1^st number: 1 9/21, 2^nd number: 14 0/5

30/21 - 70/5 is -88/7.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 5 is 105

Next, find the equivalent fraction of both fractional numbers with denominator 105
For the 1st fraction, since 21 × 5 = 105,
30/21 = 30 × 5/21 × 5 = 150/105
Likewise, for the 2nd fraction, since 5 × 21 = 105,
70/5 = 70 × 21/5 × 21 = 1470/105
Subtract the two like fractions:
150/105 - 1470/105 = 150 - 1470/105 = -1320/105
After reducing the fraction, the answer is -88/7

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