Subtract 70/15 from 7/42, Solve 7/42

Subtract 70/15 from 7/42

1^st number: 7/42, 2^nd number: 4 10/15

7/42 - 70/15 is -9/2.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 15 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 42 × 5 = 210,
7/42 = 7 × 5/42 × 5 = 35/210
Likewise, for the 2nd fraction, since 15 × 14 = 210,
70/15 = 70 × 14/15 × 14 = 980/210
Subtract the two like fractions:
35/210 - 980/210 = 35 - 980/210 = -945/210
After reducing the fraction, the answer is -9/2

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