Subtract 7/20 from 36/21, Solve 1 15/21

Subtract 7/20 from 36/21

1^st number: 1 15/21, 2^nd number: 7/20

36/21 - 7/20 is 191/140.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 20 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 21 × 20 = 420,
36/21 = 36 × 20/21 × 20 = 720/420
Likewise, for the 2nd fraction, since 20 × 21 = 420,
7/20 = 7 × 21/20 × 21 = 147/420
Subtract the two like fractions:
720/420 - 147/420 = 720 - 147/420 = 573/420
After reducing the fraction, the answer is 191/140
In mixed form: 151/140

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