Subtract 28/70 from 81/45, Solve 1 36/45

Subtract 28/70 from 81/45

1^st number: 1 36/45, 2^nd number: 28/70

81/45 - 28/70 is 7/5.

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

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 45 × 14 = 630,
81/45 = 81 × 14/45 × 14 = 1134/630
Likewise, for the 2nd fraction, since 70 × 9 = 630,
28/70 = 28 × 9/70 × 9 = 252/630
Subtract the two like fractions:
1134/630 - 252/630 = 1134 - 252/630 = 882/630
After reducing the fraction, the answer is 7/5
In mixed form: 12/5

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