Subtract 21/45 from 75/42, Solve 1 33/42

Subtract 21/45 from 75/42

1^st number: 1 33/42, 2^nd number: 21/45

75/42 - 21/45 is 277/210.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 45 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 42 × 15 = 630,
75/42 = 75 × 15/42 × 15 = 1125/630
Likewise, for the 2nd fraction, since 45 × 14 = 630,
21/45 = 21 × 14/45 × 14 = 294/630
Subtract the two like fractions:
1125/630 - 294/630 = 1125 - 294/630 = 831/630
After reducing the fraction, the answer is 277/210
In mixed form: 167/210

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