Subtract 84/45 from 28/70, Solve 28/70

Subtract 84/45 from 28/70

1^st number: 28/70, 2^nd number: 1 39/45

28/70 - 84/45 is -22/15.

Find the least common denominator or LCM of the two denominators:
LCM of 70 and 45 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 70 × 9 = 630,
28/70 = 28 × 9/70 × 9 = 252/630
Likewise, for the 2nd fraction, since 45 × 14 = 630,
84/45 = 84 × 14/45 × 14 = 1176/630
Subtract the two like fractions:
252/630 - 1176/630 = 252 - 1176/630 = -924/630
After reducing the fraction, the answer is -22/15

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