Subtract 16/80 from 70/42, Solve 1 28/42

Subtract 16/80 from 70/42

1^st number: 1 28/42, 2^nd number: 16/80

70/42 - 16/80 is 22/15.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 80 is 1680

Next, find the equivalent fraction of both fractional numbers with denominator 1680
For the 1st fraction, since 42 × 40 = 1680,
70/42 = 70 × 40/42 × 40 = 2800/1680
Likewise, for the 2nd fraction, since 80 × 21 = 1680,
16/80 = 16 × 21/80 × 21 = 336/1680
Subtract the two like fractions:
2800/1680 - 336/1680 = 2800 - 336/1680 = 2464/1680
After reducing the fraction, the answer is 22/15
In mixed form: 17/15

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