In the complex plane, the two given points are represented by

and

. The midpoint would then be

which represents the complex number

.
If paul moved his market 2 units left and 3 units down his new location would be (1,5) in order for it to be the location (0,6) he would of had to move it 3 units left and 2 units down. so he had it backwards. I hope this helps!
It's the same as multiplying a number by 1.5
The value of the 7 in the hundredths place is 10 the value of the 7 in the thousandths place. The value of the 7 in the tens place is 10 times the value of the 7 in the ones place. The value of the 7 in the hundreds place is 10 times the value of the 7 in the tens place.
Hope this helped!
Nate