Subtract 4/80 from 40/70, Solve 40/70

Subtract 4/80 from 40/70

40/70 - 4/80 is 73/140.

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

Next, find the equivalent fraction of both fractional numbers with denominator 560
For the 1st fraction, since 70 × 8 = 560,
40/70 = 40 × 8/70 × 8 = 320/560
Likewise, for the 2nd fraction, since 80 × 7 = 560,
4/80 = 4 × 7/80 × 7 = 28/560
Subtract the two like fractions:
320/560 - 28/560 = 320 - 28/560 = 292/560
After reducing the fraction, the answer is 73/140

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