Subtract 21/24 from 90/42, Solve 2 6/42

Subtract 21/24 from 90/42

1^st number: 2 6/42, 2^nd number: 21/24

90/42 - 21/24 is 71/56.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 24 is 168

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 42 × 4 = 168,
90/42 = 90 × 4/42 × 4 = 360/168
Likewise, for the 2nd fraction, since 24 × 7 = 168,
21/24 = 21 × 7/24 × 7 = 147/168
Subtract the two like fractions:
360/168 - 147/168 = 360 - 147/168 = 213/168
After reducing the fraction, the answer is 71/56
In mixed form: 115/56

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