Subtract 15/90 from 24/21, Solve 1 3/21

Subtract 15/90 from 24/21

1^st number: 1 3/21, 2^nd number: 15/90

24/21 - 15/90 is 41/42.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 90 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 21 × 30 = 630,
24/21 = 24 × 30/21 × 30 = 720/630
Likewise, for the 2nd fraction, since 90 × 7 = 630,
15/90 = 15 × 7/90 × 7 = 105/630
Subtract the two like fractions:
720/630 - 105/630 = 720 - 105/630 = 615/630
After reducing the fraction, the answer is 41/42

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