Subtract 21/80 from 42/7, Solve 6 0/7

Subtract 21/80 from 42/7

1^st number: 6 0/7, 2^nd number: 21/80

42/7 - 21/80 is 459/80.

Find the least common denominator or LCM of the two denominators:
LCM of 7 and 80 is 560

Next, find the equivalent fraction of both fractional numbers with denominator 560
For the 1st fraction, since 7 × 80 = 560,
42/7 = 42 × 80/7 × 80 = 3360/560
Likewise, for the 2nd fraction, since 80 × 7 = 560,
21/80 = 21 × 7/80 × 7 = 147/560
Subtract the two like fractions:
3360/560 - 147/560 = 3360 - 147/560 = 3213/560
After reducing the fraction, the answer is 459/80
In mixed form: 559/80

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