Subtract 9/72 from 70/42, Solve 1 28/42

Subtract 9/72 from 70/42

1^st number: 1 28/42, 2^nd number: 9/72

70/42 - 9/72 is 37/24.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 72 is 504

Next, find the equivalent fraction of both fractional numbers with denominator 504
For the 1st fraction, since 42 × 12 = 504,
70/42 = 70 × 12/42 × 12 = 840/504
Likewise, for the 2nd fraction, since 72 × 7 = 504,
9/72 = 9 × 7/72 × 7 = 63/504
Subtract the two like fractions:
840/504 - 63/504 = 840 - 63/504 = 777/504
After reducing the fraction, the answer is 37/24
In mixed form: 113/24

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