Subtract 20/7 from 90/24, Solve 3 18/24

Subtract 20/7 from 90/24

1^st number: 3 18/24, 2^nd number: 2 6/7

90/24 - 20/7 is 25/28.

Find the least common denominator or LCM of the two denominators:
LCM of 24 and 7 is 168

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 24 × 7 = 168,
90/24 = 90 × 7/24 × 7 = 630/168
Likewise, for the 2nd fraction, since 7 × 24 = 168,
20/7 = 20 × 24/7 × 24 = 480/168
Subtract the two like fractions:
630/168 - 480/168 = 630 - 480/168 = 150/168
After reducing the fraction, the answer is 25/28

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