Subtract 10/15 from 40/21, Solve 1 19/21

Subtract 10/15 from 40/21

1^st number: 1 19/21, 2^nd number: 10/15

40/21 - 10/15 is 26/21.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 15 is 105

Next, find the equivalent fraction of both fractional numbers with denominator 105
For the 1st fraction, since 21 × 5 = 105,
40/21 = 40 × 5/21 × 5 = 200/105
Likewise, for the 2nd fraction, since 15 × 7 = 105,
10/15 = 10 × 7/15 × 7 = 70/105
Subtract the two like fractions:
200/105 - 70/105 = 200 - 70/105 = 130/105
After reducing the fraction, the answer is 26/21
In mixed form: 15/21

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