Subtract 21/6 from 30/80, Solve 30/80

Subtract 21/6 from 30/80

1^st number: 30/80, 2^nd number: 3 3/6

30/80 - 21/6 is -25/8.

Find the least common denominator or LCM of the two denominators:
LCM of 80 and 6 is 240

Next, find the equivalent fraction of both fractional numbers with denominator 240
For the 1st fraction, since 80 × 3 = 240,
30/80 = 30 × 3/80 × 3 = 90/240
Likewise, for the 2nd fraction, since 6 × 40 = 240,
21/6 = 21 × 40/6 × 40 = 840/240
Subtract the two like fractions:
90/240 - 840/240 = 90 - 840/240 = -750/240
After reducing the fraction, the answer is -25/8

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