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

Subtract 1/72 from 28/42

28/42 - 1/72 is 47/72.

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,
28/42 = 28 × 12/42 × 12 = 336/504
Likewise, for the 2nd fraction, since 72 × 7 = 504,
1/72 = 1 × 7/72 × 7 = 7/504
Subtract the two like fractions:
336/504 - 7/504 = 336 - 7/504 = 329/504
After reducing the fraction, the answer is 47/72

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