Note: Given Exp , `= {15/2 + 1/2 ÷ 1/2 of 1/4 - 2/5 xx 7/3 ÷ 15/8 of (7/5 - 4/3)]` `= {15/2 + 1/2 ÷ 1/8 - 2/5 xx 7/3 ÷ 15/8 of 1/15}` `= {15/2 + 1/2 ÷ 1/8 - 2/5 xx 7/3 ÷ 1/8}` `= {15/2 + 1/2 xx 8/1 - 2/5 xx 7/3 xx 8/1}` `= {15/2 + 4 - 112/15}` `= ((225 + 120 - 224)/30)` `= 121/30` `= 4 1/30`

Note: Given Exp , `= 459/100 xx 18/10 ÷ 36/10 + 54/10 of 1/9 - 1/5` `= 459/100 xx 18/10 xx 10/36 + 3/5 - 1/5` `= 459/200 + 3/5 - 1/5` `= ((459 + 120 - 40)/200)` `= (539/200)` `= 2.695`.

Note: Given Exp , `= 3/4 ÷ 9/4 of 2/3 - (((3-2)/(6)))/(((3 + 2)/(6))) xx 10/3 + 5/6` `= 3/4 ÷ 3/2 - 1/6 xx 10/3 + 5/6` `= 3/4 xx 2/3 - 2/3 + 5/6` `= (1/2 - 2/3 + 5/6)` `= ((3 - 4 + 5)/6)` `= 4/6` `= 2/3`.

Note: Given Exp, `= (1/2 ÷ 4 + 20)/(1/2 xx 4 + 20)` `= (1/2 xx 1/4 + 20)/(2 + 20)` `= (1/8 + 20)/22` `= (161/8 xx 1/22)` `= 161/176`.

Note: Let,`(17.28 ÷ x)/(3.6 xx 0.2)=2`. Then,`= 17.28/x` `= 1.44x ` or` x= 17.28/1.44` `= 1728/144` `= 12`

Note: `(9^2 xx 18^4)/3^16` `= ((3^2)^2 xx (3 xx 3 xx 2)^4)/3^16` `= (3^4 xx 3^4 xx 3^4 xx 2^4)/3^16` `= (3^12 xx 2^4)/3^16` `= 2^4/3^4` `= 16/81`.

Note: Let,x of `1/12 = 3/8` Then,`x/12 = 3/8⇔` `x = (12 xx 3/4) = 9/2`

Note: Let ,`13/4 + 25/6 + x + 1/4 =10`. Then,`x = 10 - (13/4 + 25/6 + 1/4)` or `x =10 - ((39 + 50 + 3)/12)` `= (10 - 92/12)` `= ((120 - 92)/12)` `= 28/12` `= 7/3` `= 2 1/3`.

Note: Let,`9/2 + 19/6 + x + 7/3` `= 67/5`. Then,`x = 67/5` `= (9/2 + 19/6 + 7/3)` or `x = 67/5 - ((27 + 19 + 14)/6)` `= (67/5 - 60/6)` `= (67/5 - 10)` `= 17/5` `= 3 /2/5`

Note: Let,`47/3 xx 19/6 + 19/3` `= 205/18 + x`. Then,`893/18 + 19/3` `= 205/18 + x` or`x= (893/18 + 19/3) - 205/18` or `x = ((893 + 114)/18) - 205/18` `= ((1007 - 205)/18)` `= (802/18)` `= 44 5/9`.