What's the product of two-thirds minus one-quarter difference multiplied by the reciprocal of twenty-one?

What's the product of two-thirds minus one-quarter difference multiplied by the reciprocal of twenty-one?

The difference between two-thirds and one-quarter is five out of twelve, and the reciprocal of twenty-one is twenty-one out of twenty;
5 out of 12 times 21 out of 20 is 7 out of 16

What's the difference between 12 out of 5 and the sum of its reciprocal minus 1 out of 8 times 2 out of 3 divided by 1 out of 20?

(12/5+5/12 -1/8×2/3)÷1/20
＝(169/60－1/12)×20
＝164/60×20
＝492

11 out of 13 times 6 out of 19 plus 6 out of 13 times 8 out of 19

11 out of 13 times 6 out of 19 plus 6 out of 13 times 8 out of 19
=11/13x6/19+8/13x6/19
=(11/13+8/13)x6/19
=19/13x6/19
=6/13

5 / 9-5 / 12 + 4 / 19 = [simple calculation method]

5 / 9-5 / 12 + 4 / 19
=5 / 9 + 4 / 19-5 / 12
=1-5 / 12
=7 out of 12