Subtract 1/70 from 28/80, Solve 28/80

Subtract 1/70 from 28/80

28/80 - 1/70 is 47/140.

Find the least common denominator or LCM of the two denominators:
LCM of 80 and 70 is 560

Next, find the equivalent fraction of both fractional numbers with denominator 560
For the 1st fraction, since 80 × 7 = 560,
28/80 = 28 × 7/80 × 7 = 196/560
Likewise, for the 2nd fraction, since 70 × 8 = 560,
1/70 = 1 × 8/70 × 8 = 8/560
Subtract the two like fractions:
196/560 - 8/560 = 196 - 8/560 = 188/560
After reducing the fraction, the answer is 47/140

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