Subtract 90/42 from 20/10, Solve 2 0/10

Subtract 90/42 from 20/10

1^st number: 2 0/10, 2^nd number: 2 6/42

20/10 - 90/42 is -1/7.

Find the least common denominator or LCM of the two denominators:
LCM of 10 and 42 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 10 × 21 = 210,
20/10 = 20 × 21/10 × 21 = 420/210
Likewise, for the 2nd fraction, since 42 × 5 = 210,
90/42 = 90 × 5/42 × 5 = 450/210
Subtract the two like fractions:
420/210 - 450/210 = 420 - 450/210 = -30/210
After reducing the fraction, the answer is -1/7

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