Subtract 70/50 from 30/84, Solve 30/84

Subtract 70/50 from 30/84

1^st number: 30/84, 2^nd number: 1 20/50

30/84 - 70/50 is -73/70.

Find the least common denominator or LCM of the two denominators:
LCM of 84 and 50 is 2100

Next, find the equivalent fraction of both fractional numbers with denominator 2100
For the 1st fraction, since 84 × 25 = 2100,
30/84 = 30 × 25/84 × 25 = 750/2100
Likewise, for the 2nd fraction, since 50 × 42 = 2100,
70/50 = 70 × 42/50 × 42 = 2940/2100
Subtract the two like fractions:
750/2100 - 2940/2100 = 750 - 2940/2100 = -2190/2100
After reducing the fraction, the answer is -73/70

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