Subtract 21/42 from 8/5, Solve 1 3/5

Subtract 21/42 from 8/5

1^st number: 1 3/5, 2^nd number: 21/42

8/5 - 21/42 is 11/10.

Find the least common denominator or LCM of the two denominators:
LCM of 5 and 42 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 5 × 42 = 210,
8/5 = 8 × 42/5 × 42 = 336/210
Likewise, for the 2nd fraction, since 42 × 5 = 210,
21/42 = 21 × 5/42 × 5 = 105/210
Subtract the two like fractions:
336/210 - 105/210 = 336 - 105/210 = 231/210
After reducing the fraction, the answer is 11/10
In mixed form: 11/10

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