I don't know if you have studied equations, but I will use equations to help you solve them.

1.

Let the minuend be X and the minuend be Y. According to the meaning of the question, the following equations can be listed.

x-y= 1.5

(phase difference 1.5.

That is, the minuend x minus the minuend y)

x

y

1.5=4. 12 (the subtraction number y of the minuend x plus the difference 1.5 equals 4. 12).

By solving this system of equations, we can get

x=2.06

y=0.56

So the minuend is 2.06.

Reduced by 0.56.

2.

Let the dividend be X and the divisor be Y. According to the meaning of the question, the following equations can be listed.

0.5xy=8 1/ 100

(quotient 0.5 times dividend x)

Multiply by divisor y

Equal to 81100)

x/y=0.5

(Divided by divisor y equals quotient 0.5)

By solving this system of equations, we can get x=9/ 10.

y=9/5

That is, dividend is 9/ 10.

The divisor is 9/5

3.

1/2= 1/4

1/4

1/3= 1/6

1/6

1/x= 1/2x

1/2x