11 out of 8 minus 11 out of 15

11 out of 8 minus 11 out of 15

11 out of 8 minus 11 out of 15
=165-88 out of 120
=77 out of 120

12 times 42 = 21 times 24; 13 times 62 = 31 times 26. Observe the law of these two equations
2. Use the rule you found to write three similar equations (both numbers are double digits)!
3. If both numbers are two digits, please explain the equation conditions that satisfy the law, and list all the equations that satisfy the law
Here are three questions. Please answer them in detail,

1
Let the ten digits of two numbers be AB and CD respectively
（10a+b)*(10c+d)=(10b+a)*(10d+c)
A * C = b * D
two
12*63=21*36
13*93=31*39
14*82=41*28
three
Rule: the product of ten digits of two numbers is equal to the product of single digits of two numbers

(21 / 26 × 13 / 7 + 1 / 2) × 2 / 5
emergency

(21 / 26 × 13 / 7 + 1 / 2) × 2 / 5
=(3 / 2 + 1 / 2) × 5 / 2
=2 × 5 / 2
=5