Answer:1,504
Step-by-step explanation:
20x16=320
20x12=240
16x12=192
16x20=320
12x16=192
12x20=240
add them all the answer will be 1,504
Check the picture below.
notice the reflected gray line on the red one over the y=x line, the slope of either line across the y=x line is simply the other's upside-down.
